View Full Version : BRT OPTIMUM Barrels
In anticipation of the launch of our new series of OPTIMUM Barrels (https://www.blackrivertactical.com/concrete5/store/#!/Barrels/c/1852006/offset=0&sort=normal), we wanted to reveal some of the deeper aspects that makes these barrels some of the best options available on the market.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/855764429.jpg
First a family picture.
These all share similar characteristics.
Nothing is done to "check the box" or blindly duplicate what currently exists in the market.
Each one is purpose driven to fulfill a particular need.
I'm as much of a "just buy a Colt(well, Sionics these days) as anyone, but I do find myself using or recommending your barrels about 1/2 of the time. Interested to learn more.
And some of those deeper aspects are.....? I'm always interested. I'd at least be assured of my gun not being over/under gassed, but what else will we get?
Sorry. I clicked the LINK.
vicious_cb
09-03-18, 00:29
My personal opinion on the specs. I think you've absolutely nailed the gas system specs on your barrel the profiles are also spot on.
To nitpick but def not hating on your product which I think is great BTW. Looking at the optimum lightweight specs I feel some of the choices are strange like 5r rifling and a 1/8 twist with a hybrid target crown. Its a bit confusing since you are essentially putting match grade barrel qualities into a lightweight fighting barrel which trades weight for accuracy. You then switch it up with your MPR barrel with a 6r rifling and 1/7 twist. The pricing considering its a QPQ barrel is also pretty steep getting into the FN or DD CHF territory.
What Im getting at is Im not sure what role the barrels are supposed to fill as a hard use fighting carbine barrel or precision barrel? I see you also have a SPR/match line which makes it even more confusing.
Thanks for the feedback.
The gas systems and profiles are where much of the focus has been.
The concept with those choices in the lightweight is those specs are not an "either/or" situation where one is clearly better for target use and less better for fighting use.
The difference between a 1/7 vs 1/8 twist will not make or break anything. Far more important is the spec which is never published - bore quality.
The crown description may be a bit confusing and we may modify that nomenclature in the future.
The concept with this whole line is to re-examine the possibilities, question conventional wisdom and make the best option available, regardless of what everyone else is or isn't doing.
It certainly isn't the easy way, but innovating rarely is.
Pricing is relative to value. We believe we have a compelling set of features with the performance to justify it.
.
My personal opinion on the specs. I think you've absolutely nailed the gas system specs on your barrel the profiles are also spot on.
To nitpick but def not hating on your product which I think is great BTW. Looking at the optimum lightweight specs I feel some of the choices are strange like 5r rifling and a 1/8 twist with a hybrid target crown. Its a bit confusing since you are essentially putting match grade barrel qualities into a lightweight fighting barrel which trades weight for accuracy. You then switch it up with your MPR barrel with a 6r rifling and 1/7 twist. The pricing considering its a QPQ barrel is also pretty steep getting into the FN or DD CHF territory.
What Im getting at is Im not sure what role the barrels are supposed to fill as a hard use fighting carbine barrel or precision barrel? I see you also have a SPR/match line which makes it even more confusing.
I look at many of the additions or variations from what you find in most barrels and have come to the conclusion "Why not both?" I think as the market continues to evolve, the consumer asks more and more of what they get for their dollar in a buyer's market, and simply want more features in a given product.
For example, it absolutely may not matter, but why not have a target crown on that lightweight Barrel?
Barrel and Gas System Lengths Explained
16" EXT - The obvious general purpose length that needs no further explanation.
The EXT gas system certainly deserves some attention.
The Mid length gas system replicates the same "Power Time" as a 20" Rifle when used on a 16" barrel.
At first glance, this seems to be the correct approach, but duplicating one parameter at the expense of others leaves much to be desired.
A better approach is to scale the relevant timing parameters to keep everything in proportion.
Using this methodology, we developed the EXT gas system to be an OPTIMUM match for 16" barrels.
The EXT length is longer than Mid length but shorter than Rifle length.
This results in the widest operational envelope and the highest reliability possible.
14.0"MID - This length fulfills the need for a barrel that can be pinned and welded up to a non-NFA length using some of the longer muzzle devices available.
The conventional Mid length gas system works great with this length, as recently complete NSWC-Crane testing has proven.
Any device 2.67" or longer will work without using shims.
Some examples
BE Meyers 249F
SF Socom SF3P-556
SF Warcomp
Dead Air Flash Hider
Noveske KX5
SOLGW NOX Keymount
11.5" CAR - The middle ground in SBR lengths, it offers a great combination of velocity in a compact package that handles mixed suppressor use nicely.
The ubiquitous Carbine gas system pairs nicely with this length.
9.0" PDW - A BRT exclusive that smashes the conventional wisdom of a 10.5" minimum length for "serious use".
That conventional wisdom is true, but based on a Carbine length gas system.
We created the PDW length gas system to handle a range of very short barrels and alternative calibers by splitting the difference between existing Carbine and Pistol lengths.
A 9" barrel and the PDW gas system are a perfect match in 5.56/.223.
How about 2580 FPS from M193 and M855?
This is a great alternative to 300BLK PDWs but uses common ammunition.
Sorry Clint, I replied to your email before I saw your forum post.
Barrel and Gas System Lengths Explained
16" EXT - The obvious general purpose length that needs no further explanation.
The EXT gas system certainly deserves some attention.
The Mid length gas system replicates the same "Power Time" as a 20" Rifle when used on a 16" barrel.
At first glance, this seems to be the correct approach, but duplicating one parameter at the expense of others leaves much to be desired.
A better approach is to scale the relevant timing parameters to keep everything in proportion.
Using this methodology, we developed the EXT gas system to be an OPTIMUM match for 16" barrels.
The EXT length is longer than Mid length but shorter than Rifle length.
This results in the widest operational envelope and the highest reliability possible.
14.0"MID - This length fulfills the need for a barrel that can be pinned and welded up to a non-NFA length using some of the longer muzzle devices available.
The conventional Mid length gas system works great with this length, as recently complete NSWC-Crane testing has proven.
Any device 2.67" or longer will work without using shims.
Some examples
BE Meyers 249F
SF Socom SF3P-556
SF Warcomp
Dead Air Flash Hider
Noveske KX5
SOLGW NOX Keymount
11.5" CAR - The middle ground in SBR lengths, it offers a great combination of velocity in a compact package that handles mixed suppressor use nicely.
The ubiquitous Carbine gas system pairs nicely with this length.
9.0" PDW - A BRT exclusive that smashes the conventional wisdom of a 10.5" minimum length for "serious use".
That conventional wisdom is true, but based on a Carbine length gas system.
We created the PDW length gas system to handle a range of very short barrels and alternative calibers by splitting the difference between existing Carbine and Pistol lengths.
A 9" barrel and the PDW gas system are a perfect match in 5.56/.223.
How about 2580 FPS from M193 and M855?
This is a great alternative to 300BLK PDWs but uses common ammunition.
Clint, many companies like Surefire SOCOM RC2's , Sig Sauer, Q , Silencerco Omega 300, etc. have a 10 " inch or more minimum barrel length restriction on their suppressors when used with 5.56 NATO pressure ammo. Do you think the BRT PDW length gas system on your 9" inch PDW barrel would be easier on the suppressor, where you could get away with going an inch under their recommended minimum barrel length , or would it not change anything with that at all? I would be using the Cherry bomb muzzle brake with an Omega 300.
Barrel length restrictions for suppressors are fundamentally based on muzzle pressure vs material strength.
Those determinations are made through testing or calculations with (presumably) some safety factor.
The gas system won't change any of that.
The cherry bomb will help take some of the initial blast, so it may be fine, but getting an official OK would be worth a try.
What would SiCo say to using an aftermarket adapter and muzzle device and a shorter barrel on their suppressor?
Clint, many companies like Surefire SOCOM RC2's , Sig Sauer, Q , Silencerco Omega 300, etc. have a 10 " inch or more minimum barrel length restriction on their suppressors when used with 5.56 NATO pressure ammo. Do you think the BRT PDW length gas system on your 9" inch PDW barrel would be easier on the suppressor, where you could get away with going an inch under their recommended minimum barrel length , or would it not change anything with that at all? I would be using the Cherry bomb muzzle brake with an Omega 300.
Furbyballer
09-06-18, 10:03
Barrel and Gas System Lengths Explained
9.0" PDW - A BRT exclusive that smashes the conventional wisdom of a 10.5" minimum length for "serious use".
That conventional wisdom is true, but based on a Carbine length gas system.
We created the PDW length gas system to handle a range of very short barrels and alternative calibers by splitting the difference between existing Carbine and Pistol lengths.
A 9" barrel and the PDW gas system are a perfect match in 5.56/.223.
How about 2580 FPS from M193 and M855?
This is a great alternative to 300BLK PDWs but uses common ammunition.
Very interested in trying this barrel out and seeing how it runs mk318 62 grain otms with my sandman s.
With the 6.75” barrel, is there ammunition that would reach effective terminal velocities? Very interesting.
The 55 and 62 grain Gold Dot / Fusion loads should work nicely.
According to these threads, they expand down to ~1700 fps.
https://www.m4carbine.net/showthread.php?90278-DocGKR-question-about-Speer-Gold-Dot-55gr-5-56
https://www.m4carbine.net/showthread.php?187117-How-short-of-a-barrel-is-speer-gold-dot-223-effective
https://www.m4carbine.net/showthread.php?65698-Federal-Fusion-223-Expansion-threshold
http://www.le.vistaoutdoor.com/ammunition/speer/rifle/details.aspx?id=24446
With the 6.75” barrel, is there ammunition that would reach effective terminal velocities? Very interesting.
This should be another great combo with the 5/8-24 thread mount and unlimited barrel rating.
9.0" PDW*- A BRT exclusive that smashes the conventional wisdom of a 10.5" minimum length for "serious use".
Very interested in trying this barrel out and seeing how it runs mk318 62 grain otms with my sandman s.
BufordTJustice
09-13-18, 15:37
Damn Clint.
Dammit.
Your original 16" Optimum LW barrel has basically invalidated all my 16" middies...and I've sold them all because the 16" BRT Opt soundly outperforms all of them for my mixed use (50/50 can/no-can) when all factors are considered (weight, accuracy, recoil pulse, gas system function with suppressor). And I only ever owned properly gassed barrels from BCM, LMT, and Faxon (most recently). Even my agency supervisor, an accomplished shooter and experienced LEO, was immediately impressed at the soft recoil impulse despite my gun's light weight and using just a BE Meyers ASR flash hider mount. He kept commenting on how smooth the recoil pulse was for such a lightweight gun.
But the 9" PDW is fascinating.
And so is the slightly heavier 16" med-con continuous taper barrel.
Ugh.
I'd love to spin Pappabear's 338 Titanium sig can on one of the 11.5s. :p
Clint-How is the contrast between the MPR and SPR barrel in a suppressed, LW scoped role? Have you had a chance to test the MPR on paper? I'm tempted to look at the MPR over the SPR due to the barrel steel and subzero temperatures we see here.
ffhounddog
09-14-18, 05:27
What is the Velocity with M193 and M855 in the 6P? I was Looking at getting a 12.5 barrel because I have 3 10.5 SBRs, and kind of want the extra inch. Also why 5/8x24 threads?
We have high expectations for velocity.;)
These haven't been chrono'ed yet, but the 11.5" should be similar to a normal 12.5".
Larger 5/8-24 threads are stronger and better, especially when suppressors are involved.
Any 30 cal suppressor will work and quite a few 5.56 QD suppressors have 5/8-24 mounts available for them.
The 5/8-24 SilencerCo ASR Mount works with the Specwar 556, Specwar 556K, Saker 556, Saker 556K.
The 5/8-24 AAC 51T mount works with the M4-2000, 556-SD and Mini-4.
The 5/8-24 Griffin Taper mount works with the Reece 5 and Optimus Micro w/ optional taper mount interface.
What is the Velocity with M193 and M855 in the 6P? I was Looking at getting a 12.5 barrel because I have 3 10.5 SBRs, and kind of want the extra inch. Also why 5/8x24 threads?
ffhounddog
09-14-18, 12:24
Is the weight of the barrel with the gas block?
The 11.5" Barrel is 24.5oz with gas block.
Is the weight of the barrel with the gas block?
ffhounddog
09-14-18, 13:38
I just ordered one. Thanks, for the info. Probably should have had you pin it on there.
They'll both cycle great with identical EXT gas system configurations.
The MPR is 3.5 ounces lighter and will handle extremes better due to the material and finish.
The SPR is thicker at the chamber, however so there shouldn't be much real world concern with cold temps.
It's hard to go wrong; they're both really great choices.
Clint-How is the contrast between the MPR and SPR barrel in a suppressed, LW scoped role? Have you had a chance to test the MPR on paper? I'm tempted to look at the MPR over the SPR due to the barrel steel and subzero temperatures we see here.,
That thing's a monster!
I bet it suppresses well.
I'd love to spin Pappabear's 338 Titanium sig can on one of the 11.5s. :p
BufordTJustice
09-16-18, 11:31
They'll both cycle great with identical EXT gas system configurations.
The MPR is 3.5 ounces lighter and will handle extremes better due to the material and finish.
The SPR is thicker at the chamber, however so there shouldn't be much real world concern with cold temps.
It's hard to go wrong; they're both really great choices.
,
My buddy, for whom I built a BRT Optimum 16" gen-1 centered gun, loved it!
Forged upper and lower, BRT EXT Optimum barrel and MicroPin BRT gas block, ALG rounded top handguard (the exact model escapes me; it was mlok, lol), PWS H2 Buffer, Sprinco Blue action spring, std nitride carrier with Sprinco 5-coil extractor spring, and Precision Armament AFAB 556 (current generation). PA ACSS 3x prism fakeCog on top.
With full power federal Brown box M193, the first thing my buddy blurted out (in that barely controlled, childlike fashion) was "this damn thing kicks less than my 10/22!!!!" with a fairly dumb grin on his face. Things devolved from there.... including grown men giggling.
It basically just vibrates in your hand. With .223 pressure AE Ammo it feels like it's short stroking, but ejection is strong @ 3:30-4:00 and it locks back on empty even with no shoulder purchase. Brass collects in a bucket if you don't move.
No way to get an SR15 experience in a quality package (that will fu&$€#%ing run with reliability) for less. I've shot several SR15's (and have a deep love and respect for them that borders on fanboyism). But this is knocking on that door for much less.
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Maybe I missed it, but only SBR barrels have 5/8-24 threads?
Will a 556 SOCOM fit on a 762 SOCOM mount?
TexasAggie2005
09-16-18, 13:26
Will a 556 SOCOM fit on a 762 SOCOM mount?
I don't believe so. I've read that Surefire designed it so a 7.62 can will fit on a 5.56 mount, but not vice versa.
The "default" thread is 5/8-24, except for light barrels with .625 gas blocks and specials like the 14.0" Mid that are designed for a specific set of muzzle devices.
Maybe I missed it, but only SBR barrels have 5/8-24 threads?
The "default" thread is 5/8-24, except for light barrels with .625 gas blocks and specials like the 14.0" Mid that are designed for a specific set of muzzle devices.
Using a A2 FH and a A5H2 with Colt rifle spring, what sort of ammo is that gas port spec’d for on the 14” Mid? The weakest ammo I want to shoot with it is Fusion MSR. Hottest is M855.
The "default" thread is 5/8-24, except for light barrels with .625 gas blocks and specials like the 14.0" Mid that are designed for a specific set of muzzle devices.
You're killin me
Which combo are you looking for?
You're killin me
We haven't ported the 14.0" yet, but it should perform similarly to the 16", which runs at full reliability margin with most .223 and all 5.56 brass cased ammo.
The PMC bronze and Wolf 55gr steel case are the lowest pressure and work a little better with an A5H1 buffer.
The beauty of our OPTIMUM configurations is there's minimal cycling variation between the lightest and heaviest pressure loads.
Fired brass comes out looking nearly new, with a near complete absence of extractor pull marks, ejector swipes or deflector dings.
Using a A2 FH and a A5H2 with Colt rifle spring, what sort of ammo is that gas port spec’d for on the 14” Mid? The weakest ammo I want to shoot with it is Fusion MSR. Hottest is M855.
They'll both cycle great with identical EXT gas system configurations.
The MPR is 3.5 ounces lighter and will handle extremes better due to the material and finish.
The SPR is thicker at the chamber, however so there shouldn't be much real world concern with cold temps.
It's hard to go wrong; they're both really great choices.
,
Sounds like I have 1st world problems :D A shooting buddy is at the same crossroads as me on this one. I think I'll grab one and he'll grab the other and try to do a head to head comparison. We'll have to flip a coin on who gets what.
What are the projectioned dates for delivery? N/M, it says October.
Somehow I completely missed the LPR Barrel...
Which combo are you looking for?
The 14” looks good. I just don’t want to have to buy a 7.62 can for the 11.5”
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We haven't ported the 14.0" yet, but it should perform similarly to the 16", which runs at full reliability margin with most .223 and all 5.56 brass cased ammo.
The PMC bronze and Wolf 55gr steel case are the lowest pressure and work a little better with an A5H1 buffer.
The beauty of our OPTIMUM configurations is there's minimal cycling variation between the lightest and heaviest pressure loads.
Fired brass comes out looking nearly new, with a near complete absence of extractor pull marks, ejector swipes or deflector dings.
I’ll go ahead and preorder that, then. Sounds like what I am looking for.
What are your thoughts on a good rail for the 9"?
What are your thoughts on a good rail for the 9"?
KAC URX4 8”
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KAC URX4 8”
Excellent
What are your thoughts on a good rail for the 9"?
Any 7" rail will work fine.
An 8" rail will work perfectly, although the selection is somewhat limited.
Most 9" rails will work, but will cover the first 5/8" of the muzzle device, which may limit the functionality of many devices and suppressor mounting options.
This is a basic 7" rail over the proof of concept PDW barrel.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/885486371.jpg
What are your thoughts on a good rail for the 9"?
I like these. They are lightweight , have a 1.900" inch long barrel nut, are easy to install and have a good handguard to barrel nut attachment method. Either handguard below would work fine with a 9" inch barrel.
https://slrrifleworks.com/index.php?route=product/product&path=66_106_134_135&product_id=1217
https://slrrifleworks.com/index.php?route=product/product&path=66_106_134_135&product_id=660
snackgunner
09-18-18, 15:22
Clint how soon will we be able to order the suppressor gas drive BRT 11.5" OPTIMUM CQB Barrel??? It says sold out
KAC URX4 8”
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FWIW, the URX4 is an 8.5" rail. If you're planning to run a can on the gun, you may need to add a spacer behind the muzzle device. It's possible but VERY close to the end of the handguard.
Just received confirmation back from Surefire tech support:
The SOCOM 762 will fit on both 556 and 762 mounts, while the SOCOM 556 will only fit on 556 mounts.
Will a 556 SOCOM fit on a 762 SOCOM mount?
The 14” looks good. I just don’t want to have to buy a 7.62 can for the 11.5”
We had a few extra details to work out on the suppressor barrels.
They're up for order now (http://www.blackrivertactical.com/concrete5/store/#!/BRT-11-5-OPTIMUM-CQB-Barrel-Suppressor-Gas-Drive/p/110419568/category=1852006).
Clint how soon will we be able to order the suppressor gas drive BRT 11.5" OPTIMUM CQB Barrel??? It says sold out
ffhounddog
09-18-18, 18:54
What is the big difference between the 11.5s?
gunnerblue
09-18-18, 20:28
FWIW, the URX4 is an 8.5" rail. If you're planning to run a can on the gun, you may need to add a spacer behind the muzzle device. It's possible but VERY close to the end of the handguard.
Its actual length is 8.75” per KAC’s website, making it even less of an option.
snackgunner
09-18-18, 20:29
What is the big difference between the 11.5s?
The 11.5 suppresor barrel states in description:
BRT Suppressor barrels are designed to work best with 30 caliber suppressors using full pressure 5.56 ammunition and the following buffer systems: VLTOR A5H2, Rifle and Carbine H2.
The other 11.5 barrel doesnt have this in its desciption.
Its actual length is 8.75” per KAC’s website, making it even less of an option.
My URX4 rail measures just under 8.5"
Correct.
The suppressor version has an extra small gas port to support dedicated suppressed operation.
The 11.5 suppresor barrel states in description:
BRT Suppressor barrels are designed to work best with 30 caliber suppressors using full pressure 5.56 ammunition and the following buffer systems: VLTOR A5H2, Rifle and Carbine H2.
The other 11.5 barrel doesnt have this in its desciption.
Thanks for the range report.
The consistency and smoothness is really remarkable.
The Perma-Grin a pretty normal result after shooting an OPTIMUM barrel :D
My buddy, for whom I built a BRT Optimum 16" gen-1 centered gun, loved it!
Forged upper and lower, BRT EXT Optimum barrel and MicroPin BRT gas block, ALG rounded top handguard (the exact model escapes me; it was mlok, lol), PWS H2 Buffer, Sprinco Blue action spring, std nitride carrier with Sprinco 5-coil extractor spring, and Precision Armament AFAB 556 (current generation). PA ACSS 3x prism fakeCog on top.
With full power federal Brown box M193, the first thing my buddy blurted out (in that barely controlled, childlike fashion) was "this damn thing kicks less than my 10/22!!!!" with a fairly dumb grin on his face. Things devolved from there.... including grown men giggling.
It basically just vibrates in your hand. With .223 pressure AE Ammo it feels like it's short stroking, but ejection is strong @ 3:30-4:00 and it locks back on empty even with no shoulder purchase. Brass collects in a bucket if you don't move.
BufordTJustice
09-22-18, 12:39
Thanks for the range report.
The consistency and smoothness is really remarkable.
The Perma-Grin a pretty normal result after shooting an OPTIMUM barrel [emoji3]
It's KAC small-port levels of smoothness.
My buddy actually shot his 10/22 back to back against his BRT rig. Even with full house Nato pressure federal xm193, he swears his BRT rig both: 1) shoots softer in terms of rearward recoil and 2) has less axial movement of the reticle.
He described the reticle of the 3x PA FakeCOG ACSS as just "vibrating on target" on his BRT 16" rig.
He said he's watching bullet impacts from offhand shots at 150 yards even with a relaxed stance and cannot wait to take a deer with it this season. He'll be using 75gr Gold Dots.
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It's KAC small-port levels of smoothness.
My buddy actually shot his 10/22 back to back against his BRT rig. Even with full house Nato pressure federal xm193, he swears his BRT rig both: 1) shoots softer in terms of rearward recoil and 2) has less axial movement of the reticle.
He described the reticle of the 3x PA FakeCOG ACSS as just "vibrating on target" on his BRT 16" rig.
He said he's watching bullet impacts from offhand shots at 150 yards even with a relaxed stance and cannot wait to take a deer with it this season. He'll be using 75gr Gold Dots.
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I've only shot one rifle like that. It was a 3gunner's rifle set up around a specific load on the ragged edge of function. And in accordance with Murphy, it malfunctioned during a big match he was doing well in. I'm actually about to throw a SF muzzle brake on my BRT Optimum build for the incoming SOCOM suppressor, looking forward to it.
Clint- Is there any performance loss running the 7.62 covert comp on the 5.56 16" SPR barrel (I already ordered) since the new barrels come with the larger 5/8 threads?
The 7.62 works fine, but the Covert Comp 6X (https://www.blackrivertactical.com/concrete5/store/#!/BRT-Covert-Comp-6X/p/112555144/category=1799361) is the best choice for all barrels with 5/8-24 threads.
We put the 6X on pre-order with free shipping, so you can grab one on a separate order.
Clint- Is there any performance loss running the 7.62 covert comp on the 5.56 16" SPR barrel (I already ordered) since the new barrels come with the larger 5/8 threads?
This is a good example of the synergy between a very effective brake and the OPTIMUM gas system.
Unlike many over tuned 3 gun setups, OPTIMUM barrels maintain full reliability margin, while being extremely smooth.
Good things happen when the AR system operates at optimal timing, rather than fighting itself.
My buddy actually shot his 10/22 back to back against his BRT rig. Even with full house Nato pressure federal xm193, he swears his BRT rig both: 1) shoots softer in terms of rearward recoil and 2) has less axial movement of the reticle.
He described the reticle of the 3x PA FakeCOG ACSS as just "vibrating on target" on his BRT 16" rig.
I've only shot one rifle like that. It was a 3gunner's rifle set up around a specific load on the ragged edge of function. And in accordance with Murphy, it malfunctioned during a big match he was doing well in. I'm actually about to throw a SF muzzle brake on my BRT Optimum build for the incoming SOCOM suppressor, looking forward to it.
You guys are pushing me to complete my stalled upper build.
The parts I have on hand are:
BRT 16" Light Optimum barrel/gas block/ gas tube
BCM M4 upper receiver
ALG 12" V2 M-LOK Handguard
Sionics phosphate BCG
Trijicon 1-4 Accupower in a Warne X-SKEL fixed mount
The parts I still need are:
Charging handle
Muzzle device
I plan on a simple forged charging handle and an A2 flash hider.
I want to take the barrel/gas block in to my friendly neighborhood machinist and get them drilled for a pin (I have BRT pins on hand as well), and to pick up a reaction rod. I put my last upper together with a "clamshell" and was underwhelmed.
The lower I will pair it with is currently an A5 H2 setup with a Larue MBT two-stage trigger.
It should be a nice set up when I finish it.
Andy
P.S. I should be able to make some valid comparisons - I also have a 16" BCM mid length and a 16" FN/PSA barreled carbine with the gas drive "corrected" via BRT port.
OPTIMUM Profile Explained
Efficiency is a hot topic these days, whether it be "efficiency of motion" when practicing tactical skills or the fuel efficiency and range of your favorite SHTF vehicle.
The OPTIMUM profile could be described as "efficiency of design", producing maximum stiffness for any given weight.
It's easy to make a very stiff barrel by just piling on the material to make a very thick profile that weighs too much.
It is often said the .GOV profile is backwards, being thinner near the chamber and thicker towards the muzzle.
This is true, but mostly in the case of simple bending of the muzzle while holding the chamber.
The good real world performance can be partially explained its good performance in other types of bending.
We developed a few standard tests to compare the performance of various profiles under simulated loading.
Both deflection and stress levels are evaluated.
A balanced barrel will perform well across all three tests.
We used the 16" MID GOV profile as a baseline of performance for comparing the OPTIMUM profiles.
The 16" mid length and 16" M4 versions perform nearly identically.
Test one holds the barrel extension fixed while loading the muzzle downward with 10 pounds of force.
This represents simple bending. Stress intensity is shown. (Green arrows are fixtures. Purple arrows are forces)
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/910276099.jpg
As expected, the GOV profile performs relatively poorly in test one.
The thin area between the chamber and gas block is highly stressed (shown in green, yellow and red) compared to the rest of the barrel (shown in blue).
An OPTIMUM profile of the same weight would be 20% stiffer.
Our MPR profile adds 2 ounces and is 55% stiffer in this test with a much less intense and more evenly distributed stress area.
Test two holds the barrel extension fixed (like in test one) while loading the muzzle with a bending torque that attempts to force the barrel into an "S" or question mark like shape.
This torque is produced from a combination of a downward force of 140 pounds at the muzzle and an upward force of 140 pounds at the thread shoulder.
This represents a more complex bending that may be similar to barrel whip with a suppressor attached.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/910276104.jpg
The GOV profile does better in test two, thanks to the relatively large diameter towards the muzzle.
The thinner chamber area and the muzzle threads show the areas of most stress.
Our MPR profile improves on this already good performance by measuring 43% stiffer in this test and showing much more even stress distribution along the full length.
Test three holds the muzzle threads fixed while loading the breech downward with 5 pounds of force, basically the opposite of test 1.
This is again simple bending, but really stresses critical muzzle area.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/910276111.jpg
The GOV profile also does pretty will in test three, but shows very high stresses directly under the muzzle thread shoulder.
This is largely the result of the mismatch between the small 1/2-28 threads and the much thicker portion of the barrel directly behind the thread shoulder.
Our MPR profile bests this with a 21% improvement is stiffness in this test and nearly 50% lower stress at the muzzle thread shoulder, thanks to the sturdy 5/8-24 threads and careful contouring behind the shoulder.
Suppressor Ready Threads
There are several features required to properly support suppressor attachment.
Obviously the threads and shoulder need to be concentric and square to the bore.
Tighter clearance thread pitch assures good alignment of the muzzle device and the bore.
Most suppressor mount muzzle devices require indexing.
This is almost always accomplished via shims.
The Precision Armament shims are among the best, using a single thick shim, rather than a stack of paper thin shims.
The junction of the threads and thread shoulder must allow the shim to sit flat against the shoulder, while also supporting the shim's inner diameter to keep it concentric.
OPTIMUM barrels have all these features and more.
In addition, most OPTIMUM barrels utilize larger 5/8-24 threads, which create a much stronger connection and affect the bore much less than common 1/2-28 threads.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/910903173.jpg
Clint, can you comment on the ballistics and reliability of the 9” and 6.75” offerings?
Sent from my iPhone using Tapatalk
Sure,
The ballistics were touched on previously.
The prototype 9" made 2580 fps on M193 and M855 with standard rifling.
The velocity should be higher with the hybrid poly rifling.
The 6.75" should be above 2300 fps.
These are both quite useful with Federal Fusion ammo, which performs nicely above 1700 fps.
As part of our normal first article inspection, we'll be chronographing the production barrels and adding the results to the product descriptions.
The 9" PDW is light recoiling and easily stomps any 9mm or 300 BLK for flat trajectory within 200 yards.
We haven't done statistical reliability testing, per se.
However, using our mathematical gas drive model that was also the basis of the EXT gas system, we calculated the proper relationship between the 9" barrel and PDW gas system, as well as the required port size.
We nailed the port size on the first try and it operates exactly as expected with nice 3:30-4:00 ejection with all tested ammo.
When the timing ratios and gas drive are properly setup, maximum reliability is the natural result.
This is the essence of OPTIMUM gas drive.
Clint, can you comment on the ballistics and reliability of the 9” and 6.75” offerings?
BufordTJustice
09-27-18, 11:42
I've only shot one rifle like that. It was a 3gunner's rifle set up around a specific load on the ragged edge of function. And in accordance with Murphy, it malfunctioned during a big match he was doing well in. I'm actually about to throw a SF muzzle brake on my BRT Optimum build for the incoming SOCOM suppressor, looking forward to it.
Well this one worked with a limp wrist and no shoulder purchase.
Sent from my iPhone using Tapatalk
BufordTJustice
09-27-18, 11:45
This is a good example of the synergy between a very effective brake and the OPTIMUM gas system.
Unlike many over tuned 3 gun setups, OPTIMUM barrels maintain full reliability margin, while being extremely smooth.
Good things happen when the AR system operates at optimal timing, rather than fighting itself.
Yeah, it was actually nearly identical to my buddy's 3-gun rig the uses a much heavier Stretch-16 barrel that also uses a longer-than-mid gas barrel.
Sent from my iPhone using Tapatalk
I just got home from zeroing and shooting the 16" Light Optimum upper I assembled last night. Details are in an earlier post to this thread, but it has an A2 flash hider and A5 system with standard/A5H2 buffer.
It ran perfectly with my mild 55 gr handloads and Hornady Frontier M193 and 75 gr HP 5.56 loads. The reliability and soft shooting were anticipated when I picked that barrel.
What I was not expecting is how "flat" it shoots. I was zeroing the 1-4 accupower with a very light hold and the gun seemed to move less than my 20" Faxon Gunner on the same lower, didn't "bounce" on the rest at all.
I was also suprised at how well it shot, given the modest magnification even at 50 m.
I'm definitely looking forward to shooting this upper some more.
Andy
P.S. Neither my shooting or camera skills resemble Stickman's, but here is a quick snap.
https://i.imgur.com/sls6VlB.jpg
everready73
09-30-18, 20:12
I just got home from zeroing and shooting the 16" Light Optimum upper I assembled last night. Details are in an earlier post to this thread, but it has an A2 flash hider and A5 system with standard/A5H2 buffer.
It ran perfectly with my mild 55 gr handloads and Hornady Frontier M193 and 75 gr HP 5.56 loads. The reliability and soft shooting were anticipated when I picked that barrel.
What I was not expecting is how "flat" it shoots. I was zeroing the 1-4 accupower with a very light hold and the gun seemed to move less than my 20" Faxon Gunner on the same lower, didn't "bounce" on the rest at all.
I was also suprised at how well it shot, given the modest magnification even at 50 m.
I'm definitely looking forward to shooting this upper some more.
Andy
P.S. Neither my shooting or camera skills resemble Stickman's, but here is a quick snap.
https://i.imgur.com/sls6VlB.jpg
Looks like a nice setup. Would be interested in some accuracy results if you have time once you shoot some more.
Out of curiosity what spring are you running with the A5 system. Sprinco green, tubbs, Colt rifle ? I have been doing a lot of reading on the right spring and still can't figure out what I want to run
Looks like a nice setup. Would be interested in some accuracy results if you have time once you shoot some more.
Out of curiosity what spring are you running with the A5 system. Sprinco green, tubbs, Colt rifle ? I have been doing a lot of reading on the right spring and still can't figure out what I want to run
Perhaps start with the Colt spring/A5H2 and make adjustments as needed from there.
Looks like a nice setup. Would be interested in some accuracy results if you have time once you shoot some more.
Out of curiosity what spring are you running with the A5 system. Sprinco green, tubbs, Colt rifle ? I have been doing a lot of reading on the right spring and still can't figure out what I want to run
Thanks!
I am intererested too. Whenever I get time, I will borrow the 4-12 VXII that's mounted on my 20" rifle and do some serious shooting. The accupower is a nice optic, but I need more scope to shoot groups at 100 yards/meters or farther.
I'm running a standard BCM rifle spring in the A5.
It's probably heresy, but I don't plan on trying to tune it.
I'm building it as a second upper for my 20" rifle and envision it as a general purpose carbine. Perfection can be the enemy of good, and it's pretty good now.
Andy
Clint-Do you think the 5.56 SPR barrel gives up anything to the 223 Wylde barrel in terms of accuracy? My buddy's 5.56 barrel arrived and it looks AWESOME. Intended ammo is BH 5.56 TMK or TMK reloads. I'm looking forward to running it against the MPR barrel.
No, the 556 MOD0 chamber is similar to the Wylde.
It should love the heavy projectiles, especially when reloaded.
Clint-Do you think the 5.56 SPR barrel gives up anything to the 223 Wylde barrel in terms of accuracy? My buddy's 5.56 barrel arrived and it looks AWESOME. Intended ammo is BH 5.56 TMK or TMK reloads. I'm looking forward to running it against the MPR barrel.
The green is a good spring, but requires a little more gas drive to fully compress and increases bolt closing speed too.
The A5H2 with standard rifle spring is the baseline that all our barrels are setup for.
We also verify function with a straight up CAR system just to cover all the bases.
Everyone is certainly free to play around with combinations other than the A5H2/rifle, but in general there's no need and no real gains to be had with an OPTIMUM barrel.
Out of curiosity what spring are you running with the A5 system. Sprinco green, tubbs, Colt rifle ? I have been doing a lot of reading on the right spring and still can't figure out what I want to run
Perhaps start with the Colt spring/A5H2 and make adjustments as needed from there.
everready73
10-05-18, 07:26
Thanks Clint, that is what i will do.
snackgunner
10-08-18, 11:01
Eta on delivery for 11.5 suppressor bbls?
Barrels are getting chambered this week, so probably 4 weeks.
ffhounddog
10-11-18, 09:05
Now I need to wait until November...Great. Just getting a standard 11.5 because I like max reliability. Just got my SOLGW Flash Hider for my Dead Air in the mail.
The A5H2 with standard rifle spring is the baseline that all our barrels are setup for.
Everyone is certainly free to play around with combinations other than the A5H2/rifle, but in general there's no need and no real gains to be had with an OPTIMUM barrel.
I took the gun out yesterday for some more shooting. We shot some mild-ish 55gr. reloads, 55 gr Frontier and 62 gr Fiocci rounds, around 200 rounds total. It ran like a top with all the ammo and is just a pleasure to shoot (A5 H2 standard rifle spring).
As I was packing up, I found a steel cased round in my shooting bag and fired it. The bolt didn't lock back on the empty mag, which took me aback momentarily then I remembered that Clint has clearly stated the that the underpowered steel ammo was not what the barrels are designed for.
For me, the 16" light barrel is a winner.
Andy
Clint, what kind of accuracy can we expect from the 14” with match ammo?
Sent from my iPhone using Tapatalk
We should have some info first thing next week, as we'll be wringing out a test barrel for velocity, accuracy and port size.
Clint, what kind of accuracy can we expect from the 14” with match ammo?
Sent from my iPhone using Tapatalk
ffhounddog
10-19-18, 10:19
VA Arms was going to assemble my upper for me now just waiting on the barrel and hopefully they are still there before they close the doors. I have the Aero upper receiver, KAC URX II 10.75, LMT BCG, Dead Air/SOLGW flash hider (It was a drunk buy dam you Bulleit)
and a BCM charging handle. This will turn into my go to SBR when the Barrel shows...Oh KAC rear sight and a Aim point Comp M4 because I have being using a CompM4 for years now.
everready73
10-19-18, 10:44
VA Arms was going to assemble my upper for me now just waiting on the barrel and hopefully they are still there before they close the doors. I have the Aero upper receiver, KAC URX II 10.75, LMT BCG, Dead Air/SOLGW flash hider (It was a drunk buy dam you Bulleit)
and a BCM charging handle. This will turn into my go to SBR when the Barrel shows...Oh KAC rear sight and a Aim point Comp M4 because I have being using a CompM4 for years now.
If they are done myself and sa few others on the site have sent stuff out to John Thomas at Retro Arms Works. He does great work with good pricing and fast turnaround times. For example, I sent an upper for assembly on a Friday and had it back the next week. Believe it was $30-35 for the assembly. Has also done some pin/weld for me and they look really nice (much better than ADCO for example). I know it doesn't affect function, but shows his attention to detail
Just shoot him an email if you need another option, always replies quickly
John Thomas is great. Finest pin/weld in industry. But he doesn’t have a URX wrench (at least not two months ago). D Wilson is a KAC gunsmith and does a great job too at good prices. (https://www.dwilsonmfg.com/store/c1/store).
Test barrel update:
We did chrono and function testing with a 14.5" test barrel made from the same Hybrid Poly Rifled blanks.
Velocity was compared to an 16" OPTIMUM Light 5R 1/8 barrel, an OEM type 16" barrel and an 11.5" Chrome lined barrel.
ProChrono Chrony @ 15'
3 shot averages
40 degrees F
IMI M193*
14.5 TB: 2989 fps
16 OptL: 2967 fps
16 OEM: 2978 fps
11.5 CL: 2715 fps
* this newer IMI M193 in 20 round boxes seems ~100 fps slower than previously.
Previous batches in 30 round boxes have consistently turned in 3079 fps.
Wold Gold 55gr
14.5 TB: 2949 fps
16 OptL: 2896 fps
16 OEM: 2958 fps
11.5 CL: 2629 fps
GGG SS109 (M855)
14.5 TB: 2898 fps
16 OptL: 2888 fps
16 OEM: 2904 fps
11.5 CL: 2659 fps
Wolf WPA 55gr
14.5 TB: 2777 fps
16 OptL: 2797 fps
16 OEM: 2816 fps
11.5 CL: 2550 fps
IMI 77gr OTM MOD1
14.5 TB: 2669 fps
16 OptL: 2614 fps
16 OEM: 2668 fps
11.5 CL: ---- fps
Bottom line, the 14.5" poly barrel shows equivalent velocities to standard rifled 16" barrels.
Function was perfect with our pistol test lower equipped with an A5H2 buffer system.
everready73
10-26-18, 16:02
Looks good Clint. Did you do any accuracy testing yet?
It's interesting that the 5r rifling in the 16" Optimum barrel did not increase velocity over the OEM barrel.
I know it's a sample of one and understand the significance of the 14.5" velocities.
Andy
The first session we wanted to get port sizing and function dialed in first and then look at velocity gain.
We didn't look at accuracy yet, but these should be very good.
Bore Quality is a major factor in accuracy and these 6P blanks are excellent.
Clint, are you going to post velocities and accuracy results for the 9"?
That's the plan.
M193 velocities around 2650 seem realistic.
The 16" and 14" flavors are down to a couple pieces left.
Anyone on the fence may want to pull the trigger before they're gone.
These can also be built into uppers with ALG or SLR hand guards.
ffhounddog
11-06-18, 13:26
Late November now for a BRT 11.5" OPTIMUM CQB Barrel;....dang I wanted to run this in my cold weather class in the beginning of DEC in the WV mountains.
snackgunner
11-08-18, 12:06
Late November now for a BRT 11.5" OPTIMUM CQB Barrel;....dang I wanted to run this in my cold weather class in the beginning of DEC in the WV mountains.
You saying these barrels that were on pre order and were supposed to ship in October are now shipping late November?
ffhounddog
11-08-18, 13:13
Yes at least per the website, mine is. https://www.blackrivertactical.com/concrete5/store/#!/BRT-11-5-OPTIMUM-CQB-Barrel-PREORDER/p/110110072/category=1852006
I guess its lack of interest because I wanted the standard 11.5 not the suppressed 11.5.
I doubt its lack of interest. Some of the barrels are almost sold out.
The 16" and 14" flavors are down to a couple pieces left.
Anyone on the fence may want to pull the trigger before they're gone.
These can also be built into uppers with ALG or SLR hand guards.
Are they shipping? I have a 16" on order.
Barrels are headed out for QPQ this week.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/937917326.jpg
Here are a few videos showing our OPTIMUM Light barrel in 2Gun competition with Jason P Brown at the helm.
The third one shows the best view.
https://www.instagram.com/p/Bp8xqsWHUNq/
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/940429964.jpg
ffhounddog
11-13-18, 13:53
happy happy joy joy! cannot wait for the 11.5 CAR barrel now! New LMT BCG waiting on this new barrel.
Barrels are headed out for QPQ this week.
Very cool, can't wait to see the finished product.
snackgunner
11-26-18, 20:26
You guys have a Black Friday sale?
You guys have a Black Friday sale?
Yup.
http://www.blackrivertactical.com/concrete5/store/
Here is the news letter link.
https://mailchi.mp/6fdf1f60712e/cyber-monday
Still expecting a ship date on those 11.5" gas drive barrels by end of month?
Also - is the 23.1 oz for those including the gas block/gas tube? Or just the barrel assembly itself?
Excited to get mine!
Barrels are getting the hot dip this week, so we're currently projecting to be shipping out the week before Christmas.
The weight is just the barrel assembly. These are medium contour for strength and accuracy.
Still expecting a ship date on those 11.5" gas drive barrels by end of month?
Also - is the 23.1 oz for those including the gas block/gas tube? Or just the barrel assembly itself?
Excited to get mine!
Any plans for a normal 14.5 in either a LW or medium contour?
Any plans for a normal 14.5 in either a LW or medium contour?
Normal?
Normal?
Sorry. Standard 14.5 as opposed to your 14. I don't think that one would work with my G MK16 rail if I wanted to suppress it.
Most likely yes on the 14.5, as we've received strong interest in the very similar 14.0, which were done as a special request for a dealer.
Most likely yes on the 14.5, as we've received strong interest in the very similar 14.0, which were done as a special request for a dealer.
Neat info. I went the 14" route because it was compatible with the specific suppressor mount I was already going to use. I had wondered if it wasn't to give certain people a shorter non-nfa combo.
Most likely yes on the 14.5, as we've received strong interest in the very similar 14.0, which were done as a special request for a dealer.
I’m definitely interested in a 14 or 14.5
Neat info. I went the 14" route because it was compatible with the specific suppressor mount I was already going to use. I had wondered if it wasn't to give certain people a shorter non-nfa combo.
The 14.0 meets minimum length with muzzle devices 2.67" or longer.
BE Meyers 249F
SF Socom SF3P-556
SF Warcomp
Dead Air Flash Hider
Noveske KX5
SOLGW NOX Keymount
The 14.5 opens up quite a bit more options for compatible muzzle devices.
The 14.0 meets minimum length with muzzle devices 2.67" or longer.
BE Meyers 249F
SF Socom SF3P-556
SF Warcomp
Dead Air Flash Hider
Noveske KX5
SOLGW NOX Keymount
I'll have to break out the calipers when I get home. I have the SF SOCOM muzzle brake on the shelf, and approximately 9 weeks until the can arrives. The brake is listed at 2.7", hopefully that's an accurate measurement.
Most likely yes on the 14.5, as we've received strong interest in the very similar 14.0, which were done as a special request for a dealer.
That’s good to know, I’d be all about the 14” if the MK16 was 13” and I didn’t want to use the closed tine WarComp.
Sent from my iPhone using Tapatalk
I'll have to break out the calipers when I get home. I have the SF SOCOM muzzle brake on the shelf, and approximately 9 weeks until the can arrives. The brake is listed at 2.7", hopefully that's an accurate measurement.
*If*, the barrel is right at 14.000" inches, and *if* the barrel's thread length from the end of the barrel to the shoulder is the standard .625"length spec and *if* your SF SOCOM brake is right at 2.7" inches long, it should put the barrels total length right at 16.075" measured from the bolt face to the end of the muzzle.
*If*, the barrel is right at 14.000" inches, and *if* the barrel's thread length from the end of the barrel to the shoulder is the standard .625"length spec and *if* your SF SOCOM brake is right at 2.7" inches long, it should put the barrels total length right at 16.075" measured from the bolt face to the end of the muzzle.
It'll be sent to be pinned and welded by someone who will ensure it's within regs. As long as the threads are standard, I expect it to work. I threaded the brake onto a barrel and it added 2.1" at a minimum, no timing involved. If the project doesn't work out I'll use my current 16" Optimum barrel with the Warcomp installed as a host until we get the 14" barrel sorted out. I shoot 3-4k rifle a year, so barrels get replaced eventually.
*If*, the barrel is right at 14.000" inches, and *if* the barrel's thread length from the end of the barrel to the shoulder is the standard .625"length spec and *if* your SF SOCOM brake is right at 2.7" inches long, it should put the barrels total length right at 16.075" measured from the bolt face to the end of the muzzle.
Our lengths are accurate and that math is correct.
Additionally, there will be a timing shim.
Also, while the "name plate" length is correctly measured from breech face to muzzle, the ATF measures to the bolt face, which adds ~.125.
In short, this combo should easily be long enough.
For the next batch, we could do either 14.0 or 14.5
Currently leaning toward 14.5" with 1/2-28 threads to ensure compatibility with the most muzzle devices for pinning.
Thoughts?
For the next batch, we could do either 14.0 or 14.5
Currently leaning toward 14.5" with 1/2-28 threads to ensure compatibility with the most muzzle devices for pinning.
Thoughts?
What would the timeline be on that? Two months, 12?
*If*, the barrel is right at 14.000" inches, and *if* the barrel's thread length from the end of the barrel to the shoulder is the standard .625"length spec and *if* your SF SOCOM brake is right at 2.7" inches long, it should put the barrels total length right at 16.075" measured from the bolt face to the end of the muzzle.
Definitely measure the brake with calipers to verify. The 3 prong warcomp was longer than the listed length on Surefire's website when I measured it.
gunnerblue
12-01-18, 00:20
For the next batch, we could do either 14.0 or 14.5
Currently leaning toward 14.5" with 1/2-28 threads to ensure compatibility with the most muzzle devices for pinning.
Thoughts?
Very interested in a 14.5.” It seems to me that most muzzle devices are the same OAL with regards to 1/2-28 vs 5/8-24 or am I wrong?
For the next batch, we could do either 14.0 or 14.5
Currently leaning toward 14.5" with 1/2-28 threads to ensure compatibility with the most muzzle devices for pinning.
Thoughts?
I'd prefer the 14.0", but would buy either.
Just finished up a Suppressor Compatibility Chart for 5/8-24 threads.
Looks like Sig and Surefire are the only holdouts.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/951372366.jpg
I'd definitely be into a 14.5 with 1/2x28 threads to try on my URGI, just curious on the timeline as I already have a WarComp waiting to be put on it.
The majority are the same length, while some of the 5/8-24 are slightly longer.
The 14.5" allows a wide variety of choices.
Very interested in a 14.5.” It seems to me that most muzzle devices are the same OAL with regards to 1/2-28 vs 5/8-24 or am I wrong?
We'll be starting production on the next batch first thing in January.
I'd definitely be into a 14.5 with 1/2x28 threads to try on my URGI, just curious on the timeline as I already have a WarComp waiting to be put on it.
We'll be starting production on the next batch first thing in January.
Well that’s super tempting, I’ll definitely be paying attention to this thread more.
ETA - Are you planning on going 1/7 like the 14" or 1/8 like the 16"?
Sent from my iPhone using Tapatalk
The plan going forward is for all versions to use the 1/7 match blanks.
Well that’s super tempting, I’ll definitely be paying attention to this thread more.
ETA - Are you planning on going 1/7 like the 14" or 1/8 like the 16"?
The plan going forward is for all versions to use the 1/7 match blanks.
Very nice.
BufordTJustice
12-21-18, 15:20
The plan going forward is for all versions to use the 1/7 match blanks.
What rifling will they use? The 5R in my 1:8 Optimized is just a lights out shooter.
Sent from my iPhone using Tapatalk
The hybrid poly rifling.
Should be even better.
What rifling will they use? The 5R in my 1:8 Optimized is just a lights out shooter.
No, the 556 MOD0 chamber is similar to the Wylde.
It should love the heavy projectiles, especially when reloaded.
Must have missed this but is this mod0 chamber you reference modeled in any way after John Noveskes' mod0 chamber which AFAIK is designed for mk262 ammo specifically.
NVMD, I see it's simply a standard NATO t.56 chamber and not a super tight match chamber.
Has the first batch of the pre-ordered barrels shipped out yet ? Thanks
Barrels will be shipping out this week!
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/966835997.jpg
Excellent! I look forward to getting some range reports.
I keep trying to chase down my UPS guy....
I can't wait!!!
I keep trying to chase down my UPS guy....
I can't wait!!!
This one is Yours...
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/967749166.jpg
This one is Yours...
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/967749166.jpg
Don't tease!!!
I'm going to be like a dog waiting for its owner to come home as the UPS guy drives up the road...
All pre order barrels (except for complete uppers) are shipped.
snackgunner
01-05-19, 00:06
Can't wait!
Got mine! It’s very nice. Put it on my Centurion build.
Was thinking of going with a Sprinco spring.
Clint, what color Sprinco spring with my H2 carbine buffer?
The baseline spring is standard strength, so mil-spec or Sprinco white.
Thank you sir!
https://farm5.staticflickr.com/4830/39717761943_7946e5777b_k.jpg (https://flic.kr/p/23vHUT2)Untitled (https://flic.kr/p/23vHUT2) by Cory Fluck (https://www.flickr.com/photos/101418915@N07/), on Flickr
https://i.imgur.com/J3wpCnp.jpg
Ready to be scoped.
https://i.imgur.com/J3wpCnp.jpg
Ready to be scoped.
14" long barrel?
https://i.imgur.com/J3wpCnp.jpg
Ready to be scoped.
Very nice... What’s the star lower. I like that a lot.
@fledge
What length is your barrel? Gun looks really nice.
That's an 11.5" OPTIMUM CQB (https://www.blackrivertactical.com/concrete5/store/#!/BRT-11-5-OPTIMUM-CQB-Barrel/p/110110072/category=1852006)
https://i.imgur.com/J3wpCnp.jpg
Ready to be scoped.
14" long barrel?
@fledge
What length is your barrel? Gun looks really nice.
Yep, 11.5. (13.5 with dead air device). Can’t wait to run this.
Star is the BCM logo I had laser engraved. This should be the logo on all their lowers rather than the cartoony wording they have now.
https://i.imgur.com/0GsBk87.jpg
[QUOTE=Clint;2658191]We have high expectations for velocity.;)
These haven't been chrono'ed yet, but the 11.5" should be similar to a normal 12.5".
Larger 5/8-24 threads are stronger and better, especially when suppressors are involved.
Two of the many reasons I also chose the 11.5 barrel.
Yep, 11.5. (13.5 with dead air device). Can’t wait to run this.
Star is the BCM logo I had laser engraved. This should be the logo on all their lowers rather than the cartoony wording they have now.
https://i.imgur.com/0GsBk87.jpg
Looks awesome, they definitely should do it that way. The cartoon font is old though, I believe.
Looks awesome, they definitely should do it that way. The cartoon font is old though, I believe.
Good to know they changed it. This is a pre-cartoon logo lower.
The 10.6 centurion rail matches well with this length barrel too.
Is it possible to do a FSB on the 11.5" barrel?
Bob Sacamano
01-13-19, 17:15
Is it possible to do a FSB on the 11.5" barrel?
+1 for a pinned FSB option.
While I like my free floated builds I feel more and more like including FSBs on my rifles. I don't run a PEQxx so irons are my back up sighting system. I particularly like the idea on 11.5" barrels.
I too would love an option for FSB at least with the lighter profile barrels. I’d still free-float, but as with TKDpreacher, I like to retain the front sight secured to barrel, unless used as an exclusively scoped carbine.
Yes,
The CQB profile is designed to work with a FSB.
Is it possible to do a FSB on the 11.5" barrel?
Yes,
The CQB profile is designed to work with a FSB.
Smart move, IMHO. And even in 2019 barrels with a FSB are still preferred by some of us.
Furbyballer
01-14-19, 14:55
Anyone have any time on one of their new 9in 556 barrels?
snackgunner
01-15-19, 07:25
@Clint, ETA on 14" barrels?
We're fresh out, as the rest of those 14" went to Weapon Outfitters.
Our new barrels are live on their site.
https://www.weaponoutfitters.com/black-river.html
https://www.weaponoutfitters.com/black-river-optimum-mpc-barrel-14.html
https://www.weaponoutfitters.com/black-river-optimum-mpc-barrel-gb-14.html
@Clint, ETA on 14" barrels?
@Clint
Are you planning to offer a chrome-lined barrels? 14.5" Medium profile like your BRT SPR would be great. I'd buy one especially with the pinned block.
55612
14" mid-length build. Just a beauty queen report so far. I'll add the MRO at the range since it's on my primary, and replace the LMT front sight later. D.Wilson Manufacturing did the P&W, door to door was a week. I was hoping to shoot it in the -14 degree weather, but strep came to visit. Weighs in at approx 7# according to a Lyman trigger gauge.
I'll have the MPR build up later.
How do these barrels compare to a 16 inch faxon gunner or pencil barrel? Im looking for a barrel for a light weight build. Specifically I'm looking at the 16 inch BRT optimum light barrel.
How do these barrels compare to a 16 inch faxon gunner or pencil barrel? Im looking for a barrel for a light weight build. Specifically I'm looking at the 16 inch BRT optimum light barrel.
It depends how you compare them. IMHO the BRT is superior in all ways except weight.
The BRT optimum light barrel weighs 2 ounces more than a Faxon Gunner, 5 ounces more than a Faxon Pencil - all 16" tubes and advertised weights. The Gunner and more so the BRT have a heavier profile behind the gas block than the pencil barrel. They should be more accurate and have less POI shift due to temperature.
The BRT barrel has 5R rifling, which should result in higher velocities, may result in better accuracy, and will foul less.
The Faxon barrels will be generously gassed, and will happily run Tula .223 steel case ammo. On the flip side, they will not shoot as smoothly as the BRT.
My BRT 16" Optimum Light barrel did not lock the bolt back on the single round of Tula I fired through it. It does function perfectly with my mild reloads through IMI M193 ammo with an A5H2 buffer.
My BRT also shoots very soft/flat, noticeably so compared to my other 16" ARs. I have not fired it for accuracy, but it showed some real potential when I zeroed it's 1-4 optic at 100 yards/meters.
The BRT barrel includes a gas tube and is available from the manufacturer with a pinned low profile gas block.
Andy
P.S. I should add that I have a 20" Faxon Gunner barrel. It has proven to be accurate and reliable.
everready73
01-20-19, 17:12
How do these barrels compare to a 16 inch faxon gunner or pencil barrel? Im looking for a barrel for a light weight build. Specifically I'm looking at the 16 inch BRT optimum light barrel.
Andy covered it really well. I believe Faxon is the OEM for these but built to BRT spec. I would think the QC/QA is better with brt as well
The biggest difference is the improved gas system. Both the length and port sizing should make for a very smooth shooting and reliable gun.
The rifling and extra attention to detail are added bonuses as well .
so I guess the only downsides are slightly increased weight, increased cost and being iffy on super crap ammo. The slightly increased mass of the barrel is probably the better way to go and I wont really be using steel cased ammo. Plenty of cheap brass ammo out there. When funds allow, I'll probably get this barrel over the Faxon. Id rather have a smoother firing gun at the cost of 2 ounces. Is there any user test data to demonstrate these barrels accuracy capabilities? With the factory pinned gas block, do I just tap in the pin once everything is assembled?
Andy covered it really well. I believe Faxon is the OEM for these but built to BRT spec. I would think the QC/QA is better with brt as well
The biggest difference is the improved gas system. Both the length and port sizing should make for a very smooth shooting and reliable gun.
The rifling and extra attention to detail are added bonuses as well .
The gas system is what really attracts me to this barrel.
With the taper of the barrel shifting the weight to the back, the 2 oz is going to feel very negligible, imho.
yea I thought so as well. But everyone always says ounces=pounds but I don't think ill be hiking with this thing anytime soon.
One of these barrels is currently in the EE for a good price that I’d jump on if I weren’t tapped out currently.
yea I thought so as well. But everyone always says ounces=pounds but I don't think ill be hiking with this thing anytime soon.
That's true...but that's also big picture. If your hand guard, barrel, gas block, muzzle device, sighting system, and stock are all individually heavier than needed you'll quickly add pounds to your build. That's different than purposely choosing a specific component for its attributes, such as the barrel in this case.
My 16" Optimum barreled rifle with RDS weighs approx 7.5#, and I could probably use a lighter iron rear sight than a LMT rear, a lighter 12" hand guard than my 13" hand guard, and a lighter stock than the clubfoot Imod to get under 7# if that was my goal.
so I guess the only downsides are slightly increased weight, increased cost and being iffy on super crap ammo. The slightly increased mass of the barrel is probably the better way to go and I wont really be using steel cased ammo. Plenty of cheap brass ammo out there. When funds allow, I'll probably get this barrel over the Faxon. Id rather have a smoother firing gun at the cost of 2 ounces. Is there any user test data to demonstrate these barrels accuracy capabilities? With the factory pinned gas block, do I just tap in the pin once everything is assembled?
The optional pinned gas block has set screws (my barrel is dimpled) that you tighten, then install the pin.
Please keep in mind that I fired a single Tula round to see if it would lock the bolt to the rear, and that was with a new BCG. Tula is pretty weak stuff.
You may try a search for accuracy results.
The optional pinned gas block has set screws (my barrel is dimpled) that you tighten, then install the pin.
Please keep in mind that I fired a single Tula round to see if it would lock the bolt to the rear, and that was with a new BCG. Tula is pretty weak stuff.
You may try a search for accuracy results.
IIRC, Tula would barely cycle mine, but not lock back. I have an AGB on mine, though. I set it so standard brass 223 locks back when loosely held, and I think weaker PMC has to be shouldered to lock back.
That's true...but that's also big picture. If your hand guard, barrel, gas block, muzzle device, sighting system, and stock are all individually heavier than needed you'll quickly add pounds to your build. That's different than purposely choosing a specific component for its attributes, such as the barrel in this case.
My 16" Optimum barreled rifle with RDS weighs approx 7.5#, and I could probably use a lighter iron rear sight than a LMT rear, a lighter 12" hand guard than my 13" hand guard, and a lighter stock than the clubfoot Imod to get under 7# if that was my goal.
Yea I see what your saying. I plan to save weight everywhere else I can. Right now i'm thinking about going with the alg v2 rail or the brigand arms carbon fiber black edge tube. I was planning on going with a faxon gunner/pencil barrel but I think Id rather have a smoother shooting gun that doesn't open up as much at the expense of 3 to 5 ounces. It all trade offs with guns. To further save weight, Im planning on using a bcm mod 0 stock and an upper without the forward assist. But nothing is set in stone.
IIRC, Tula would barely cycle mine, but not lock back. I have an AGB on mine, though. I set it so standard brass 223 locks back when loosely held, and I think weaker PMC has to be shouldered to lock back.
is not being able to shoot steel ammo reliably important? I'm somewhat new to this. on ammoseek, brass mil spec ammo seems pretty cheap.
is not being able to shoot steel ammo reliably important? I'm somewhat new to this. on ammoseek, brass mil spec ammo seems pretty cheap.
It's personal preference. For me, brass cased ammo is easier to get and less trouble in the long run. I don't worry about steel case. In fact, I don't know steel cased ammo will reliably run any of my current ARs.
is not being able to shoot steel ammo reliably important? I'm somewhat new to this. on ammoseek, brass mil spec ammo seems pretty cheap.
It's not to me, but I had a couple boxes of it for some reason. I can see the appeal of shooting cheapest possible ammo, but quality ammo is as affordable as I've seen it in recent years.
is not being able to shoot steel ammo reliably important? I'm somewhat new to this. on ammoseek, brass mil spec ammo seems pretty cheap.
The only steel cased .223/5.56 ammo I have ever purchased was to see if my ARs would run it reliably. Curiosity killed the cat, you know.
My 16" Optimum barrel functions correctly with mild reloads (24.5 gr TAC w/55 gr FMJ), and that is all I needed it to do.
Andy
It's personal preference. For me, brass cased ammo is easier to get and less trouble in the long run. I don't worry about steel case. In fact, I don't know steel cased ammo will reliably run any of my current ARs.
I think brass is affordable enough to avoid it. My understanding Is that steel on steel contact is rougher on your gun considering that these bullets may also have bimetal jackets along with their steel cases. Also the steel doesn't obturate and create a seal as well as brass since its a much stiffer metal and I think that's what accounts for a lot of the low power you see from those rounds along with sub par powder charges. But its alluring to be able to shoot anything if you really had to for some reason.
Maybe some of you folks can help me with something I've been thinking about.
I'm looking at the 16" Optimum SPR barrel from BRT to build into a sort of dual role/scoped carbine. I've wanted to do this build for a while and I'm starting to price out parts. I've been wanting to try the EFAB from Precision Armament. With the Optimum SPR barrel having 5/8-24" threads I would have to use the .308 version of the EFAB.
My question is, will the larger EFAB be effective at all when used with the smaller caliber? I'll have to reach out to Precision Armament for their thoughts as well but I figured I'd ask you all as well.
Thanks,
W.
My question is, will the larger EFAB be effective at all when used with the smaller caliber? I'll have to reach out to Precision Armament for their thoughts as well but I figured I'd ask you all as well.
Same question from me, but for the SF Warcomp/FH muzzle devices in 7.62. The 5/8 thread size on the Optimum (mine anyway) necessitates this caliber for this line of muzzle devices to be compatible, will that degrade their (the muzzle devices, not the barrel) effectiveness at doing what they're supposed to do?
Most 7.62 muzzle devices are still plenty effective.
All things being equal, one can expect a slight reduction in brake effectiveness using a larger bore.
But 7.62 muzzle devices are often larger overall and therefore more effective than their 5.56 versions.
These two factors tend to offset each other.
Our SPR barrel topped with a 30 cal Q cherry bomb moves very little and can be pretty much fired one handed.
We're finishing up a customer build with an MPR barrel and a Dead Air key-mount brake which should perform similarly.
I'm looking at the 16" Optimum SPR barrel from BRT to build into a sort of dual role/scoped carbine. I've been wanting to try the EFAB from Precision Armament. With the Optimum SPR barrel having 5/8-24" threads I would have to use the .308 version of the EFAB.
My question is, will the larger EFAB be effective at all when used with the smaller caliber?
Same question from me, but for the SF Warcomp/FH muzzle devices in 7.62. The 5/8 thread size on the Optimum (mine anyway) necessitates this caliber for this line of muzzle devices to be compatible, will that degrade their (the muzzle devices, not the barrel) effectiveness at doing what they're supposed to do?
Thanks Clint!
That helps put me at ease. Still in the preliminary planning stages but hopefully I'll be picking up one of your barrels soon.
For any one interested,
I emailed Precision Armament about their EFAB's performance when used on a barrel like this. Here is their response:
While I don't have any exact numbers for you, we have tested this. There will be some performance degradation, but it's certainly less than 10% off of our advertised percentages (in terms of flash suppression and recoil reduction). Another option would be to use the 5.56 EFAB, and re-thread it with 5/8x24. Just throwing that out there!
If it could be rethreaded, that would be most ideal for me. Anyone know a smith willing to do that sort of thing?
Also, for anyone wanting to go from 1/2-28 to 5/8-24 threads. This might be another option for you.
https://precisionarmament.com/product-category/muzzle-devices/thread-adapters/
This might be another option for you.
https://precisionarmament.com/product-category/muzzle-devices/thread-adapters/
I think this is the reverse of what he is asking for- this takes a 1/2 barrel to 5/8, whereas he has a 5/8 barrel and wants a 1/2 muzzle device.
Or I'm completely off base
For anyone else curious about the 5/8 vs 1/2 thread thing on 5.56 barrels like these, I did some digging and found this thread from last year:
https://www.m4carbine.net/showthread.php?205786-5-8x24-threads-on-5-56-223
Clint and others in that thread make it easy to understand.
What kind of accuracy or precision do these barrels typically see? And what type of ammo do they like the best? Specifically the BRT optimum light 16 inch barrel.
What kind of accuracy or precision do these barrels typically see? And what type of ammo do they like the best?
Which barrel in particular? I'll be sighting in an MPR pretty soon.
Which barrel in particular? I'll be sighting in an MPR pretty soon.
Specifically the BRT optimum light 16 inch barrel.
55748
LW Optimum barrel:
My buddy(who is typically an excellent group shooter) shot this 200 yard group with 55gr Fiocchi ammo. He called the shot on the outside. He was a couple shooters to the right of me on the firing line when he shot the group. It's about a 4" group minus the called flyer.
Finally got out to start shooting the MPR barrel and I'm pretty happy with it. The conditions were horrid, -4 degrees and -30 Realfeel, with the wind in my face. I set a target between 55-60 yards(50 yard marker is under a snow berm, I made sure to exceed it), and started dialing in the scope. I threw several very hasty 3-shot groups while checking how the scope tracks before making a final adjustment and throwing a final 5-shot group. It's a great start, esp in such nasty conditions. Ammo was 62gr bthp handloaded, and this 30 minute range pit stop takes 1st place as the most painful range session of my life. Final group was .397 center to center according to my calipers (I measured outside edges and subtracted .223).
55833
55834
55835
Now that’s dedicat!!!
Thanks for the update.
Still planning on picking up one of Clint's SPR barrels and a SOLGW NOX, but I've also been thinking the MPR might be worth swapping into one of my other rifles.
Will some of these models be produced for some time?
Here are some OPTIMUM Chrono results to share:
Ammo was slightly older batch IMI M193 55gr FMJ that has shown proper velocities in the past.
Temp was 38F
16" MPR - 3084 fps - This is similar to or slightly better than other 16" barrels we've tested.
11.5" CQB - 2778 fps - Check.
9.0" PDW - 2546 fps - This is a seriously useful velocity from the very compact barrel. This upper cycles very nicely, just like the larger 11.5 CQB.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1000374719.jpg
Nice shooting!
Accuracy should get even better throughout the break-in process and be settled in by 200 rounds.
Finally got out to start shooting the MPR barrel and I'm pretty happy with it. The conditions were horrid, -4 degrees and -30 Realfeel, with the wind in my face. I set a target between 55-60 yards(50 yard marker is under a snow berm, I made sure to exceed it), and started dialing in the scope. I threw several very hasty 3-shot groups while checking how the scope tracks before making a final adjustment and throwing a final 5-shot group. It's a great start, esp in such nasty conditions. Ammo was 62gr bthp handloaded, and this 30 minute range pit stop takes 1st place as the most painful range session of my life. Final group was .397 center to center according to my calipers (I measured outside edges and subtracted .223).
55833
55834
55835
Clint,
Will your 16" MPR barrels be returning at some point?
Clint,
Will your 16" MPR barrels be returning at some point?
Yes, we're starting on a new run now.
These are grouping nicely with the Federal 75 TMJ
100 yards from a bipod, shaky reset and mil-spec trigger in 28 degree weather.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1006373663.jpg
New BRT OPTIMUM LPR and MPR barrels are available for pre-order.
Coupon code PRE will get you a complimentary Micro Pin Gas block.
BRT OPTIMUM LPR 16" EXT (https://www.blackrivertactical.com/concrete5/store/#!/BRT-16-OPTIMUM-LPR-Barrel-PRE-ORDER/p/111315435/category=1852006)
BRT OPTIMUM MPR 16" EXT (https://www.blackrivertactical.com/concrete5/store/#!/BRT-16-OPTIMUM-MPR-Barrel-PRE-ORDER/p/110110019/category=1852006)
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1032200629.jpg
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1032200624.jpg
Coupon code PRE will get you a complimentary Micro Pin Gas block.
Just saw that you’re using a 5/8x24 threaded muzzle. Awesome. I’ll be giving one of these a try.
Just saw that you’re using a 5/8x24 threaded muzzle. Awesome. I’ll be giving one of these a try.
The large threads are an important part of the overall profile.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/966837860.jpg
I’ve been using ARP barrels and wanting to pick up a couple extras but he seems to be moving away from the 5/8x24 threaded muzzles and moving to more light weight profiles in 5.56/223wylde. The larger muzzle size does seem to help with accuracy for lighter weight bullets with less bearing surface.
jerrysimons
03-20-19, 10:37
Thought about adding NP3 to the barrel extensions?
We are investigating alternative finishes for the barrel extensions.
Thought about adding NP3 to the barrel extensions?
Yes, we're starting on a new run now.
These are grouping nicely with the Federal 75 TMJ
100 yards from a bipod, shaky reset and mil-spec trigger in 28 degree weather.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1006373663.jpg
56504
More MPR goodness. TMK reloads gave a 4 3/16" group from 416 yards. Shooting from the top of a hay bale to get out of the snow makes a challenging rest, but it apparently works :)
Shot my 14” OPTIMUM yesterday. I don’t have any groups to post, but I can say that it is very soft shooting with M855, A1 stock with Colt rifle buffer and spring, Forward Controls Design 1815 flash hider.
A Guardsman I was shooting with pointed out the low recoil compared to her issued FN M4a1, unsolicited. She was not told anything about the rifle before shooting it. We worked on alternate supported and unsupported positions, barriers, shoulder transitions, and weak side firing.
No stoppages to report. Ambient temp was 40-50F, rainy. I’m using a Forward Controls Design (S)BCG, which is super nice. I’m curious how it will run in colder weather, since it is such a soft shooter. I’m very happy with it thus far. If it vets well, it may end up being my favorite rifle, although I plan to replace the A1 stock with an A5.
Side note: installing a pinned gas system with a URX4 is like building a ship in a bottle, but totally worth it.
Clint-other than the barrel length difference, how close are the MPR and 14" barrel in profile?
Wow!
Not sure how I missed this thread.
I’m only about 1/4 thru the thread.
I’ll finish it tonight and will have some input.
Awesome!
Sent from my iPhone using Tapatalk
Clint-other than the barrel length difference, how close are the MPR and 14" barrel in profile?
I can’t answer this directly, but the 14” with 13” URX4 Mlok about half covered with plastic rail covers, full mass BCG, forged no forward assist Aero upper, regular forged lower with CTR buttstock, H2 buffer, MBUS sights, Aimpoint PRO with covers weighs 7lb 5oz unloaded, no sling. Same upper on a no-frills lower with A1 stock weighs 7lbs 8oz.
All the profiles share similar design parameters and scaling ratios.
So, they're mostly the same, but each is slightly different.
Clint-other than the barrel length difference, how close are the MPR and 14" barrel in profile?
I like what I have read.
What would be required to make one of your barrels work in an LMT MRP upper??
That’s what I’m thinking at the moment.
Thanks.
Sent from my iPhone using Tapatalk
everready73
03-22-19, 07:49
I like what I have read.
What would be required to make one of your barrels work in an LMT MRP upper??
That’s what I’m thinking at the moment.
Thanks.
Sent from my iPhone using Tapatalk
You would have to have someone alter the barrel so it fits.. Marvin Pitts used to do it but not sure if he does. He is busy usually but you could try contacting him. I also have seen that Randall at ar15barrels.com does them
You would have to have someone alter the barrel so it fits.. Marvin Pitts used to do it but not sure if he does. He is busy usually but you could try contacting him. I also have seen that Randall at ar15barrels.com does them
Thank you kindly!
Sent from my iPhone using Tapatalk
For everyone who missed them the first time, BRT OPTIMUM 14.5 MPC barrels are also available for pre-order along with the 16" versions posted previously.
BRT OPTIMUM MPC 14.5" MID (https://www.blackrivertactical.com/concrete5/store/#!/BRT-14-5-OPTIMUM-MPC-Barrel-*-PRE-ORDER/p/134491035/category=1852006)
Coupon code PRE will score you a complimentary Micro Pin Gas block.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1037051548.jpg
55612
14" mid-length build. Just a beauty queen report so far. I'll add the MRO at the range since it's on my primary, and replace the LMT front sight later. D.Wilson Manufacturing did the P&W, door to door was a week. I was hoping to shoot it in the -14 degree weather, but strep came to visit. Weighs in at approx 7# according to a Lyman trigger gauge.
I'll have the MPR build up later.
Suppressor finally came in, and I was able to shoot it unsuppressed and suppressed for comparison. Unsuppressed, it shoots exceptionally smooth, if not obnoxiously loud due to the muzzle brake and ejects 55gr Wold Gold empties at 4:30ish. Wearing a SF 556 SOCOM RC, it ejects the empties at 2:30-3:00 and still feels smooth. I hope to get a few hundred more rounds through by June, but I'm pretty happy with the minimal functional impact from unsuppressed to suppressed.
Suppressor finally came in, and I was able to shoot it unsuppressed and suppressed for comparison. Unsuppressed, it shoots exceptionally smooth, if not obnoxiously loud due to the muzzle brake and ejects 55gr Wold Gold empties at 4:30ish. Wearing a SF 556 SOCOM RC, it ejects the empties at 2:30-3:00 and still feels smooth. I hope to get a few hundred more rounds through by June, but I'm pretty happy with the minimal functional impact from unsuppressed to suppressed.
Excellent.
Which buffer? A5H2?
Excellent.
Which buffer? A5H2?
Yes, coupled with a Sprinco Green spring. I may try an A5H3 for comparison as the rifle's primary function to to be suppressed, but I'm certainly happy with it as is. Suggestions?
Clint, not sure if you have already covered this somewhere, but what buffers do you recommend with the lightweight 16” midlength+ barrel. I’m about to complete two lowers for it, one carbine, one A5. Carbine lower has a sprinco blue. A5 lower will use a standard spring. Muzzle device is a 1815 flash hider, and I have a full mass bcg. Ammo it MUST function with is Fusion MSR. I also shoot a lot of proper 556 ammo. Edit: this rifle will never wear a suppressor. I have shorter guns for that.
Btw, my midweight 14” barrel continues to function reliably with 5.56 ammo such as M855 using H1, H2, and rifle buffers. Runs great and recoils like a .22 Hornet. I live in a warm place, so I’m not sure if it proves anything. But I’m a very happy customer. I’ve not cleaned anything in that rifle yet. Approximately 1,000 rnds.
Sounds like its running great.
We did some testing where the heavier buffer showed less ejection angle change suppressed than the lighter buffer.
The heavier buffer may smooth out the feel and is worth a try if you wanted to see.
Yes, coupled with a Sprinco Green spring. I may try an A5H3 for comparison as the rifle's primary function to to be suppressed, but I'm certainly happy with it as is. Suggestions?
Clint, not sure if you have already covered this somewhere, but what buffers do you recommend with the lightweight 16” midlength+ barrel. I’m about to complete two lowers for it, one carbine, one A5. Carbine lower has a sprinco blue. A5 lower will use a standard spring. Muzzle device is a 1815 flash hider, and I have a full mass bcg. Ammo it MUST function with is Fusion MSR. I also shoot a lot of proper 556 ammo. Edit: this rifle will never wear a suppressor. I have shorter guns for that.
Btw, my midweight 14” barrel continues to function reliably with 5.56 ammo such as M855 using H1, H2, and rifle buffers. Runs great and recoils like a .22 Hornet. I live in a warm place, so I’m not sure if it proves anything. But I’m a very happy customer. I’ve not cleaned anything in that rifle yet. Approximately 1,000 rnds.
I am sure Clint will step in, but I have used both A5H2 and Carbine H2 buffers with my light 16 Optimum barrel with standard (BCM) rifle and carbine action springs. The A5H2 was on a borrowed lower from my rifle and the new and dedicated lower has a carbine RE/H2.
My 16" Optimum has been flawless with a variety of factory 5.56 and .223 as well as modest handloads. Caveats are that I have not run it very dirty and I only shot a couple hundred rounds with the A5H2.
Andy
The 16" EXT gas system runs really well with a wide range of buffers from CAR-H to Rifle including the A5H0-A5H2.
Clint, not sure if you have already covered this somewhere, but what buffers do you recommend with the lightweight 16” midlength+ barrel. I’m about to complete two lowers for it, one carbine, one A5. Carbine lower has a sprinco blue. A5 lower will use a standard spring. Muzzle device is a 1815 flash hider, and I have a full mass bcg. Ammo it MUST function with is Fusion MSR. I also shoot a lot of proper 556 ammo. Edit: this rifle will never wear a suppressor. I have shorter guns for that.
Btw, my midweight 14” barrel continues to function reliably with 5.56 ammo such as M855 using H1, H2, and rifle buffers. Runs great and recoils like a .22 Hornet. I live in a warm place, so I’m not sure if it proves anything. But I’m a very happy customer. I’ve not cleaned anything in that rifle yet. Approximately 1,000 rnds.
I am sure Clint will step in, but I have used both A5H2 and Carbine H2 buffers with my light 16 Optimum barrel with standard (BCM) rifle and carbine action springs. The A5H2 was on a borrowed lower from my rifle and the new and dedicated lower has a carbine RE/H2.
My 16" Optimum has been flawless with a variety of factory 5.56 and .223 as well as modest handloads. Caveats are that I have not run it very dirty and I only shot a couple hundred rounds with the A5H2.
Andy
Well,
I finally took the plunge. I ordered the SPR barrel with a pinned gas block. I also ordered a Sons of Liberty NOX to pair with the barrel.
I'm very excited to get this build underway.
I'm checking interest in an 11.5" barrel with a taper at the end for a direct thread suppressor (Sig, Q as examples). It may be possible for BRT to make a run if there is enough interest. Post here or PM me if interested. Thank you.
Some examples
Shown is a 12.5" MID Taper that is FSB compatible and dedicated suppressed.
A more general purpose design would be 11.5 CAR with the same 5/8-24 taper threads.
Previous discussion here:
https://www.m4carbine.net/showthread.php?205690-Taper-Shoulder-Barrels
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1062024112.jpg
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1062024117.jpg
I'm checking interest in an 11.5" barrel with a taper at the end for a direct thread suppressor (Sig, Q as examples). It may be possible for BRT to make a run if there is enough interest. Post here or PM me if interested. Thank you.
In the referenced thread, somehow I missed this part: "adapter ring that converts the shoulder back to square, any legacy muzzle device can be used." That would solve the issue of using a standard/current MD. I think the taper would be excellent for a direct-thread can with a matching taper, and I want the 11.5" carbine-gas length version!
Clint, talk nerdy to me baby...
Curious whether or not there's anything you can share that quantifies your claim that the gas system lengths and port sizes are "optimized" for each barrel length? Very interesting product line that I feel may address what I think is the root of of all evil on the M4 platform (gas drive). Maybe something worth fiddle ****ing around with if they were so inclined.
Excited to see tapers coming up, would definitely buy a tapered 9” 300 BLK
Example of an 11.5 CAR, 25 Degree Tapered Muzzle 5/8-24 Thread
* Sig / Q compatible for 30 caliber
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1062125345.jpg
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1062125355.jpg
Using tapered barrels really seems like an excellent idea for a dedicated suppressor host.
An alternative to get the benefits of the taper mount for barrels with no tapered shoulder, is by using some components by "Q". The Plan-B suppressor mount, the cherry bomb muzzle brake and the bottle rocket enhanced muzzle brake. Available for the following suppressors.
Plan-B: OMEGA: SilencerCo Omega 300, Harvester Big Bore 338 & Hybrid | Dead Air Nomad | Energetic Armament VOX
Plan-B: SAKER: SilencerCo Saker 7.62, Saker 5.56, Saker 5.56 K & Chimera 300
Yes, these would be Sig / Q compatible.
Who's interested?
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Yes, these would be Sig / Q compatible.
Who's interested?
100% interested, something severely lacking in the barrel market right now without having to send out a barrel have the work done.
I'm in for an 11.5 with a regular gas drive.
Yes, these would be Sig / Q compatible.
Who's interested?
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/1063827312.jpg
I’d be in for a 10.3” with suppressor gas drive. I plan on using the Q plan B mount for a Turbo K.
Edit: I just put one of these in NFA jail today. The wait will hurt. Silencershop has them in stock.
I’d be in for a 10.3” with suppressor gas drive. I plan on using the Q plan B mount for a Turbo K.
How do we know Plan B will work with Turbo K?
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How do we know Plan B will work with Turbo K?
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The blast chamber of the Turbo® K is threaded to the popular 1-3/8”-24 thread which allows it to utilize many available mounting options currently on the market.
How do we know Plan B will work with Turbo K?
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Q says its compatible. If you know something else, I’m all ears.
A tapered muzzle will allow direct attachment of the following suppressors:
Q Half Nelson, Full Nelson
Sig SRD762, SRD762Ti
A 5/8-24 tapered muzzle will allow proper attachment of the following QD Mounts:
Q Cherry Bomb 7.62, which mount the Trash Panda and Thunder Chicken suppressors
Sig SRD762 QD Taper-Lok Flash Hider, SRD762 QD Taper-Lok Brake, which mount the SRD762-QD and SRD762TI-QD suppressors
The Plan-B adapter over the Cherry Bomb allows use of the following 1-3/8”-24 thread base suppressors:
SiCo Omega 300, Hybrid 46, Harvester 300
DA Nomad-30
EA VOX-S, VOX-K
REX Viribus, Fidelis
RMS Hopaii (556)
YHM Turbo-K (556)
Clint- How many of those 9" PDW barrels have you moved? How well do they function with a suppressor? I'm really interested in building an SPR with a suppressor that ends up being about the same length as my 16" carbines, but I'm nervous considering the less than stellar reputations that 5.56 barrels shorter than 10.5 hold.
The 9" PDW can run well suppressed and un-suppressed, depending on port size.
The PDW gas system is shorter than CAR and provides very good function with the 9" barrel.
You can think of the PDW as a scaled down version of the 11.5" CAR.
Both the 9" PDW and 11.5" CQB-S make great dedicated suppressed setups.
Clint- How many of those 9" PDW barrels have you moved? How well do they function with a suppressor? I'm really interested in building an SPR with a suppressor that ends up being about the same length as my 16" carbines, but I'm nervous considering the less than stellar reputations that 5.56 barrels shorter than 10.5 hold.
The 9" PDW can run well suppressed and un-suppressed, depending on port size.
The PDW gas system is shorter than CAR and provides very good function with the 9" barrel.
You can think of the PDW as a scaled down version of the 11.5" CAR.
Both the 9" PDW and 11.5" CQB-S make great dedicated suppressed setups.
I'm going to start piecing one together. I'll build a pistol first to test on, then go from there. On your website.. the picture of the 9" PDW .. is that an ALG 8" rail?
Yes, 8" ALG EMR V2X
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I'm going to start piecing one together. I'll build a pistol first to test on, then go from there. On your website.. the picture of the 9" PDW .. is that an ALG 8" rail?
Thanks. Not sure if I'm going with that rail, but it's very inexpensive and a good way to test out whether I want to go this route.
Which suppressor are you looking to pair this with?
I'm really interested in building an SBR with a suppressor that ends up being about the same length as my 16" carbines...
Which suppressor are you looking to pair this with?
I'm new to the whole suppressor world, but right now I'm looking at the Sandman S or Sandman Ti.
The rifle I am building with your 16" MPR and covert comp comes in at roughly 18" long and 34 ounces or so, plus about 4 ounces of rail, for a total of 38 ounces. .
The 9" PDW barrel, plus Keymount + Sandman Ti equals right at 17.5" and 38 ounces. Front sight will be further back as well.. so I think it will balance great.
I'm new to the whole suppressor world, but right now I'm looking at the Sandman S or Sandman Ti.
The rifle I am building with your 16" MPR and covert comp comes in at roughly 18" long and 34 ounces or so, plus about 4 ounces of rail, for a total of 38 ounces. .
The 9" PDW barrel, plus Keymount + Sandman Ti equals right at 17.5" and 38 ounces. Front sight will be further back as well.. so I think it will balance great.
Sandman Ti is direct thread. If your looking to use the Keymount, you want the Sandman S.
Sandman Ti is direct thread. If your looking to use the Keymount, you want the Sandman S.
Thanks. I missed that. An S is likely where I'll go. I want ease of moving from one rifle to the next quickly.
Shot my 16” BRT light barrel today. 86 rounds Precision One 62gr 5.56, 100 rounds P One 55gr .223, 10 rounds Fusion MSR for lock back testing. Zero stoppages with H2 and Sprinco Blue. 100% lock back on empties. 75F, rainy. Recoil was noticeably more than my 14” midweight BRT, but the muzzle stayed tight to the targets hammering triples. It currently wears a FCD 1815 flash hider. Swings between targets like a light barrel should. I’m using a URX4. Very fast transitions, and very fast splits. I bet it’ll be a total pussycat on one of my A1 rifle style lowers.
This rifle is going to see a lot of use, but the 14” midweight is my favorite of the two. Might be my favorite rifle, overall. The 16” light is probably my favorite 16” rifle, so far. We’ll see if thats still true in a few thousand. I just need a flashlight for it now.
The 14" barrel made me a believer in the P&W. If I didn't already have the 16" LW, I'd build a second 14.5" P&W if there was a LW 14.5". I never thought it'd matter, but I really notice and appreciate the shorter overall length. I do wonder if a LW 14.5" would feel like a pogo stick, though. I still need to get my pistol build done.
The 14" barrel made me a believer in the P&W. If I didn't already have the 16" LW, I'd build a second 14.5" P&W if there was a LW 14.5". I never thought it'd matter, but I really notice and appreciate the shorter overall length. I do wonder if a LW 14.5" would feel like a pogo stick, though. I still need to get my pistol build done.
I feel like the14” MPR is really at home on a registered SBR with an A2 length flash suppressor, like the 6315. Its pretty much the shortest barrel that is safe on a 13” URX4.
Curious whether or not there's anything you can share that quantifies your claim that the gas system lengths and port sizes are "optimized" for each barrel length? Very interesting product line that I feel may address what I think is the root of of all evil on the M4 platform (gas drive). Maybe something worth fiddle ****ing around with if they were so inclined.
We start with very specific relationships for the gas system and barrel length to set the overall timing.
The gas system length also determines the available Gas Drive for that barrel length.
The initial gas port size is calculated from the numerical models to produce the total Gas Drive, both suppressed and un-suppressed.
By the way, the proper Gas Drive for all possible configurations varies by only +/- 10%.
The final gas port size is verified through extensive testing using a range of buffer weights and ammo in a variety of conditions and situations.
Post #7 hits the highlights of the results.
Barrel and Gas System Lengths Explained
16" EXT - The obvious general purpose length that needs no further explanation.
The EXT gas system certainly deserves some attention.
The Mid length gas system replicates the same "Power Time" as a 20" Rifle when used on a 16" barrel.
At first glance, this seems to be the correct approach, but duplicating one parameter at the expense of others leaves much to be desired.
A better approach is to scale the relevant timing parameters to keep everything in proportion.
Using this methodology, we developed the EXT gas system to be an OPTIMUM match for 16" barrels.
The EXT length is longer than Mid length but shorter than Rifle length.
This results in the widest operational envelope and the highest reliability possible.
9.0" PDW - A BRT exclusive that smashes the conventional wisdom of a 10.5" minimum length for "serious use".
That conventional wisdom is true, but based on a Carbine length gas system.
We created the PDW length gas system to handle a range of very short barrels and alternative calibers by splitting the difference between existing Carbine and Pistol lengths.
A 9" barrel and the PDW gas system are a perfect match in 5.56/.223.
One can see the results of these proportions when viewing the whole family together.
https://dqzrr9k4bjpzk.cloudfront.net/images/812059/855764429.jpg
Well,
I finally took the plunge. I ordered the SPR barrel with a pinned gas block. I also ordered a Sons of Liberty NOX to pair with the barrel.
I'm very excited to get this build underway.
Still waiting on my barrel to ship.
In the meantime, the SOLGW NOX arrived. I didn't realize the ports weren't neutral and are timed for a righty so it will be going back. Instead, I ordered a Forward Controls 6310. I've been very happy with Roger's parts and flash hiders and I have no doubt this will be just as good. I ordered at 6:00 this morning and had tracking a bit over 3 hours later.
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