View Full Version : Highest reasonable velocity to expect from SMKs in a RECCE?
guitarist1993
10-31-13, 14:47
Since I just finished my new rifle, I'm starting work on some new loads for 3 gun. I'd like 1 MOA accuracy, with the highest velocity possible, to match up with my scope's BDC. My question is, what kind of speed should I be expecting out of 16'' barrel with 69g or 77g SMKs? I'd like to get 2800 fps if possible, but I feel like I'd be pushing the pressure too high in order to get them that fast.
It's a Wylde chamber, if that matters.
evoutfitters
10-31-13, 15:05
2800fps is REALLY pushing hard for 77gr SMKs out of a 16" barrel. More reasonable for the 77gr would be 2650fps.
Might be able to get close with the 69s.
Depends, too, on where you typically shoot. Higher elevations mean faster MVs.
guitarist1993
10-31-13, 15:22
2800fps is REALLY pushing hard for 77gr SMKs out of a 16" barrel. More reasonable for the 77gr would be 2650fps.
Might be able to get close with the 69s.
Depends, too, on where you typically shoot. Higher elevations mean faster MVs.
With my current 69 load, I'm averaging 2615 with 24g of IMR 8208. Would a powder with a faster burn rate be able to up the speed with the same charge size?
I actually haven't started working with a 77 load yet, but I've shot a good amount of MK262, and it's coming in at 2513.
I'm still getting in to reloading, sorry for the noob question.
Failure2Stop
10-31-13, 15:26
Remember that high velocity for a weight does not usually produce the best precision. 100 fps isn't really going to do much for your drops, but it can make a whole lot of difference in your groups.
Remember that high velocity for a weight does not usually produce the best precision. 100 fps isn't really going to do much for your drops, but it can make a whole lot of difference in your groups.
Totally nailed it....usually when I shoot smoking hot loads for precision measurements, they result it being at least some larger sized group measurement than the comparable slower moving load.
Also, when shooting precision or at long distance....the ultimate deciding factor when"pushing the envelope" is no questions asked the Indian himself, and his actual skill set.
The right shooter can take slow moving PRZI 75gr. HPBT w/ a 10.5" and ring it out all day long out to 700yds within a standard of 2MOA or less I'd say.
All that said, it's super easy to chase velocity, especially if your only plugging data into a dope calculator as opposed to seeing it real world on a range. 100fps in a ballistic calc can yield noticeable gains in windage drift, and elevation dope especially at the longer ranges, however again...real world and ballistic calcs are never truly dead nuts on each other.
Quickload Guesstimates
69 grain SMK, 26.0 grains Varget, 2949 fps, 20 inch barrel
69 grain SMK, 26.0 grains Varget, 2798 fps, 16 inch barrel
77 grain SMK, 24.5 grains Varget, 2777 fps, 20 inch barrel
77 grain SMK, 24.5 grains Varget, 2638 fps, 16 inch barrel
Both loads just below 60,000 psi
With a 55 grain bullet and a faster powder like H332 over 99% of the powder would be burned in a 16 inch barrel.
Its also more effective on head shots when shooting Zombies. ;)
http://i122.photobucket.com/albums/o254/bigedp51/Zmax_zps46455064.jpg
You'll be blowing primers if you get to that velocity out of a 16 barrel. Try your reticle on reasonable velocity ammo.... It may be right on the money.
You'll be blowing primers if you get to that velocity out of a 16 barrel. Try your reticle on reasonable velocity ammo.... It may be right on the money.
If he starts hot loading his brass life will go to shit also.
If he starts hot loading his brass life will go to shit also.
Yep. We did the 262 clone thing for a brief while.... switched back to a .223 max load and really sacrificed nothing.
I still run a 262 clone in new, crimped brass for home Defense... but for long range, bulk, match ammo.... there is no downside to standard pressure ammo.
I have shot a bit of 3Gun over the past 20+ years. Most matches are under 300 and knowing your trajectory does not take long. A 175 yard zero on a regular 55 grain 223 will get it done 98% of the time. Since you are shooting Minor you do yourself no favors in shooting heavy bullets. Your shot to shot splits will also be faster with a lighter pill. A good working comp is also a good investment.
Greg
guitarist1993
11-11-13, 15:27
In the matches around me, we routinely have targets out to 600 yards. I actually found out my scope BDC works better with a 200 yard zero.
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In the matches around me, we routinely have targets out to 600 yards. I actually found out my scope BDC works better with a 200 yard zero.
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That is pretty impressive. I have seen the odd 350 yard stage over the years in 3Gun but never past that. I was the SC for Oklahoma for over 10 years. We found the fun factor went way down that far out. Hard run and gun usually doesn't have the set up for that far. I would look on that as more Precision Rifle stuff. I don't know about the new generation of BDC AR scopes but I have would think someone does a version that would handle that bullet. Of course filling in the blanks with one of the On Target programs will help you convert what you really have to what it says you have. Plugging in the numbers is so much easier than the abacus I learned with.
Greg
Remember that high velocity for a weight does not usually produce the best precision. 100 fps isn't really going to do much for your drops, but it can make a whole lot of difference in your groups.
I forgot where I read it, but the writer of an article said to find the barrel natural harmonics that allow for the least standard deviation based on the flex of the barrel and the average muzzle velocity. The article went to great lengths to look at the maximum group diameter by shooting a sample of 20 rounds and looking at the average velocity and also the maximum group spread. The loads that had the bullet exit at the near extremes (I think) of the barrel flexing caused the maximum amount of time for the bullet to exit and the minimum bullet group sizes. The loads where the bullet exited near the middle of the barrel flex travel had a greater group size due to the position of the barrel having a wider range of motion.
That being said, I don't reload rifle ammo, I don't shoot long range, but it makes sense to me. I can try to graph that on a chart to illustrate what I am referring to.
guitarist1993
11-11-13, 17:31
We have more natural terrain than bays in our matches with North Texas Multigun. I'll actually be shooting a precision 3 gun match (pistol, carbine, and precision rifle) next month with shots out to 700.
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We have more natural terrain than bays in our matches with North Texas Multigun. I'll actually be shooting a precision 3 gun match (pistol, carbine, and precision rifle) next month with shots out to 700.
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I would love to belly up in that dust up. Gets my juices flowing just thinking about it.
Greg
guitarist1993
11-11-13, 18:51
I would love to belly up in that dust up. Gets my juices flowing just thinking about it.
Greg
I definitely enjoy stages that have longer range targets more than stages that don't. I like the challenge of having to slow down after going balls out.
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I forgot where I read it, but the writer of an article said to find the barrel natural harmonics that allow for the least standard deviation based on the flex of the barrel and the average muzzle velocity. The article went to great lengths to look at the maximum group diameter by shooting a sample of 20 rounds and looking at the average velocity and also the maximum group spread. The loads that had the bullet exit at the near extremes (I think) of the barrel flexing caused the maximum amount of time for the bullet to exit and the minimum bullet group sizes. The loads where the bullet exited near the middle of the barrel flex travel had a greater group size due to the position of the barrel having a wider range of motion.
That being said, I don't reload rifle ammo, I don't shoot long range, but it makes sense to me. I can try to graph that on a chart to illustrate what I am referring to.
What your getting at is the Accuracy Nodes for a barrel. Typically you'll find that most barrels have a high and low node.... where the barrel shoots best near min and max loadings.
Low S.D.s don't always translate into the best groups. And large SDs usually are the fault of the ammo. A lot of times I'll see guys just pick a load that's right down the middle of min/max. I think I too did that when I was getting started. Doing that can really short you a truly good load for your barrel.
But the bottom line is you have to go out and figure it out for each barrel.... and if you have a bad barrel, it may never shoot no matter what load you try.
My 77 load is 22 grains of AR Comp @2530fps from a 16".
I use a ACOG on it and the load is zeroed to BDC. It money from 100-300 and only shoots slightly high at 400, but still close enough for work on torso targets
Those ACOGs are so awesome for mid range shooting from 300-600 where Bullet drop becomes a real factor.
1slow01Z71
11-12-13, 21:10
I really doubt you could even get 2600 with 77s out of a 16" without destroying your brass. My 20" slings 77s at 2650 with 23.8gr of varget which isnt particularly hot but accuracy went down and the case is getting damn full at that point. Id go with a lighter bullet or a longer barrel.
I really doubt you could even get 2600 with 77s out of a 16" without destroying your brass. My 20" slings 77s at 2650 with 23.8gr of varget which isnt particularly hot but accuracy went down and the case is getting damn full at that point. Id go with a lighter bullet or a longer barrel.
Varget is an ass ache powder for .223. You can drop the charge and get a bit more into the case.... but there's so much more user friendly small kernal extrudeds to be used before dealing with Varget in .223
H322 (my favorite), XBR, LT-32, Norma 202, etc. I've used all of those for max plus loads on the Dillon 550b without a drop tube, and get no compressed charges.
I do love varget, but not for .223.
Varget is an ass ache powder for .223. You can drop the charge and get a bit more into the case.... but there's so much more user friendly small kernal extrudeds to be used before dealing with Varget in .223
H322 (my favorite), XBR, LT-32, Norma 202, etc. I've used all of those for max plus loads on the Dillon 550b without a drop tube, and get no compressed charges.
I do love varget, but not for .223.
I like the LT-32 because it meters better than long stick almost as good as ball. From what I understand it will still compress a little without any ill effects.
So are you saying it works well with .223? I've been using it with heavier 6.8 bullets but if it works well with .223 that's even better :)
We tried a little in .223 and it showed promise. We didn't knock it out of the park like with H322, but I'm sure another run at it and we could really get it dialed in.
I have a ton of H322. And with So many different projects going... I just have been trying to stick to known loads.
1slow01Z71
11-13-13, 10:36
Varget is an ass ache powder for .223. You can drop the charge and get a bit more into the case.... but there's so much more user friendly small kernal extrudeds to be used before dealing with Varget in .223
H322 (my favorite), XBR, LT-32, Norma 202, etc. I've used all of those for max plus loads on the Dillon 550b without a drop tube, and get no compressed charges.
I do love varget, but not for .223.
Agreed bbutits what I've got a lot of. I just recently got 2 pounds of 355, and I've got 1 pound of xbr. I do have 16# of wc844 but have my reservations about using milsurp for my max effort heavy pills. I had planned on using it for my stockpile of 55gr fmj stuff. Im just now getting my dillon up and running to entertain mass producing 223. When I was loading on the rovk chucker it wasn't any extra work to use varget. Now that I can load on the dillon I had planned to do some 77gr load development on a powder drop friendly powder just hadnt quite got there yet with hunting season upon us. I did plan to search through your threads to find your pet loads as it seems most like them.
Hey... Having a lot of Varget is always a good problem. :)
1slow01Z71
11-13-13, 10:46
Why do you like 322 so much better over some of the other powders that meter well? Im looking for a powder that will get me atleast 2650 out of my 20" slinging 77s and burns clean. I shoot suppressed most of the time so the cleaner the better.
H322's roots are in Benchrest, and it was once "THE" winningest powder amongst those lunatics. But H322 with Matchkings has far and away been the most accurate combo for us in .223 across the board.
The standard load I make shoots outstanding in all kinds of ARs and Bolt guns. It's a freak load with the Wolf primers where the groups size and Standard Deviations just crush everything else.
One time on High Power range, I shot a 5 round group with a stock barreled Rem 700 5R where the FLYER... The flyer opened the group up to 1/4 MOA. The Wolf primers and H322 play together unbelievably well.
1slow01Z71
11-13-13, 12:56
Guess I'll go on the hunt for some 322 and wolf primers then. I havent been able to find wolf primers in a while. Which wolf primers do you use? Theres so damn many iterations for a dang SR primer its ridiculous.
I'm running the SRMs. I'll have to grab the exact product code later. But I also read that the TULA primers are the same thing. I think the guys over on AccurateShooter mentioned that they're the same thing from the same plant.
I've also run another of the WOLF SR 223 or whatever variants. I didn't chrono those or anything solid... but didn't notice a difference either.
If I saw WOLF anything Small Rifle or TULA small rifle in a store, I'd buy it.
Check Widners. They got a shipment in about a month ago.
H322's roots are in Benchrest, and it was once "THE" winningest powder amongst those lunatics. But H322 with Matchkings has far and away been the most accurate combo for us in .223 across the board.
The standard load I make shoots outstanding in all kinds of ARs and Bolt guns. It's a freak load with the Wolf primers where the groups size and Standard Deviations just crush everything else.
One time on High Power range, I shot a 5 round group with a stock barreled Rem 700 5R where the FLYER... The flyer opened the group up to 1/4 MOA. The Wolf primers and H322 play together unbelievably well.
Mark, have you tested this combination (Wolf & H322) with the heavier 30 cal. 168/175 SMKs and if so, does it work as well as the .223 loads?
I should add that I'm more specifically inquiring about 308 data.
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guitarist1993
11-17-13, 16:10
Bit of an update here. I finally got out to chrono some ammo with my new(ish) rifle, and the results surprised me immensely. With a 62g remanufactured round I've got a few thousand of, I was hitting 2900 out my CLE recon with .223 Wylde chamber. That same round averages ~2750 out of my PSA 16" 5.56. I also took several different factory new 75 & 77 variants. Most of them (Hornady, Silver State Armory, ASYM) were around 2500 or 2600. But I had some Black Hills new MK262, and that shit was pushing 2750! I didn't have any popped primers of noticeable overpressure, but I didn't think to keep track of which brass was which round (derp).
Mark, have you tested this combination (Wolf & H322) with the heavier 30 cal. 168/175 SMKs and if so, does it work as well as the .223 loads?
I should add that I'm more specifically inquiring about 308 data.
I have not. I'm happy with Varget in .308, but I damn sure would like to try WOLF Large Rifle primers at a minimum. Just cant get my hands on a small enough quantity... without any hazmat fees.
1slow01Z71
11-19-13, 22:15
Bit of an update here. I finally got out to chrono some ammo with my new(ish) rifle, and the results surprised me immensely. With a 62g remanufactured round I've got a few thousand of, I was hitting 2900 out my CLE recon with .223 Wylde chamber. That same round averages ~2750 out of my PSA 16" 5.56. I also took several different factory new 75 & 77 variants. Most of them (Hornady, Silver State Armory, ASYM) were around 2500 or 2600. But I had some Black Hills new MK262, and that shit was pushing 2750! I didn't have any popped primers of noticeable overpressure, but I didn't think to keep track of which brass was which round (derp).
What kind of chrono are ypu using? 2750 for a 77gr out of a 16" pipe is absolutely smoking if not popped primer territory. Ihave some blackhills mk262 that runs 2650 out of my white oak armament 20" 7twist over a magnetospeed. I just dont see you having 100fps more than me with a 4" shorter barrel. My 23.8gr varget load nets 2650 as well, 2700+ is widely accepted as fairly hot territory for 77gr bullets out of 18"+ barrels much less a 16". Maybe I missed something or I've got a bum barrel.
My old Larue OBR 16" shot 2766 average with military MK262. My 24.0gr XBR load shoots 2744 average out of the same barrel. This is at 1000ft above sea level. My data shows that the real MK262 loses 22.666fps per half inch of barrel (16" down to 14.5"). The 24.0XBR load shows a 20fps loss per half inch. This holds true all the way down to my 11.5" barrel shooting the same loads under the same conditions. It has been my experience as well that the Wolf Small Rifle Magnum primers not only have almost equivalent velocities when compared to a BR4 primer, but they also have tighter ES and SD, depending on the barrel.
One final note, the 24.0XBR load out of my 11.5" barrel is hotter by 25fps over military MK262. Less pressure signs too. XBR has shown very minimal temperature sensitivity.
What kind of chrono are ypu using? 2750 for a 77gr out of a 16" pipe is absolutely smoking if not popped primer territory. Ihave some blackhills mk262 that runs 2650 out of my white oak armament 20" 7twist over a magnetospeed. I just dont see you having 100fps more than me with a 4" shorter barrel. My 23.8gr varget load nets 2650 as well, 2700+ is widely accepted as fairly hot territory for 77gr bullets out of 18"+ barrels much less a 16". Maybe I missed something or I've got a bum barrel.
1slow01Z71
11-22-13, 23:11
Guess I need to revisit my mk262 clone load and pump it up some more. I do have a pound of xbr I can try out. Right now my load is 23.8gr of varget under 77gr smks and custom comps.
Be cautious with that XBR. As I've found, and read on Accurateshooter, XBR turns on you quick when you're approaching 5.56 velocities. I had to back my 262 clone off 3 tenths to get it to quit blowing primers.
When I chrono'd the primer popper batch, it wasn't significantly faster than previous lots of ammo. If I come across my notes, I'll post more. But 23.8 grains was where 262 velocities where achieved.... but primers started letting go.
Real 262 used a ball powder of course since it's a military round, and durability is essential.
1slow01Z71
11-24-13, 12:59
Im just not understanding how he is getting 100fps more out of a 16" barrel than I am out of a 20" white oak 7 twist. I ran some blackhills 77gr over the chrono the same day I ran my 23.8gr varget load and both loads had a 10 shot average of right at 2650. Ive got varget, 335, wc844 and xbr tp play with. If need be I can track down some other powder but it seems to me my velocities are right in the neighborhood of everyone else who makes the 262 clone load. Thats why it confuses me how hes getting 2750 out of a 16", it just doesnt add up.
the_accuser
11-24-13, 18:04
H322 and 8208 xbr are my two favorite powders for 77 SMK loads. I tested various charges and primers over the last several months and concluded that all of my ARs love 23.0 gr of 8208 xbr and either a Federal 205m or Wolf small rifle magnum primer. Average velocity out of my 16" LMT MRP is 2580 fps.
Thats why it confuses me how hes getting 2750 out of a 16", it just doesnt add up.
No mention of what chrono he's using. And if i Read him right, 2513 is what he's getting from real Mk262??
I am getting almost 2,600 fps out of my SIG 556 1:7" 16" barrel with 25.0 grains of BLC-2 with Wolf SRM primer behind Barnes 70 grain TSX:
http://www.phossil.com/thom/RWS%2034%20Pellet/SIG%20Chrono.jpg
http://www.phossil.com/thom/RWS%2034%20Pellet/Barnes%2070%20Chrono.jpg
Kills hogs like nothing else out past 200 yards:
http://www.phossil.com/thom/Night%20Vision/FLIR%20T60/T60%20Backyard%20Boar/Hog%20Grapple.jpg
I use the same loading data for my SMKs, Nosler 77s, and Hornady 75s although I have not chrono'ed the OTM bullets.
1slow01Z71
11-26-13, 18:15
No mention of what chrono he's using. And if i Read him right, 2513 is what he's getting from real Mk262??
Where did he say he was getting 2513 from real mk262? That would be much more in line with what Id expect out of a 16" barrel.
I have seen numbers from an ammo company that label their mk262 clone at 2,750 fps from a 16" barrel. Many of the responses in this thread make this seem like marketing hype. Since I do no reload, I have no experience to rely on when considering this claim. Those of you who do, what do you think?
Here is another data point using a MRP Recce w/ 16" Rock 5R SS barrel using actual red box BH's Mk262.....2791 @ muzzle tested via 35P chrono.
http://i888.photobucket.com/albums/ac81/trident1982/DSC05151-2-1.jpg (http://s888.photobucket.com/user/trident1982/media/DSC05151-2-1.jpg.html)
Thanks! Not being a reloader or owning a chronograph, I have no way to know other than the information I find here.
Be cautious with that XBR. As I've found, and read on Accurateshooter, XBR turns on you quick when you're approaching 5.56 velocities. I had to back my 262 clone off 3 tenths to get it to quit blowing primers.
When I chrono'd the primer popper batch, it wasn't significantly faster than previous lots of ammo. If I come across my notes, I'll post more. But 23.8 grains was where 262 velocities where achieved.... but primers started letting go.
Real 262 used a ball powder of course since it's a military round, and durability is essential.
Markus, 77SMK, some of my notes show the H322 load out of a 16' Centurion gave us 2537 fps and XBR out of ?? ( notes don't say might have been 18' WOA) gave 2701. And our Turbo XBR load did 2750 but put eyes out with primers.
TURBO, was a hot batch of XBR. Not higher grain load.
Where did he say he was getting 2513 from real mk262? That would be much more in line with what Id expect out of a 16" barrel.
In post #3:
but I've shot a good amount of MK262, and it's coming in at 2513.
guitarist1993
11-27-13, 08:21
Sorry guys, haven't checked back in a while. Using the blue Beta Master shooting chrony. 2513 was from a commercially reloaded copy I get from a local guy, the 2750 was from factory new Black Hills Mk 262
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1slow01Z71
11-27-13, 10:58
In post #3:
Ah, good call. The post below clarifies the confusion.
Sorry guys, haven't checked back in a while. Using the blue Beta Master shooting chrony. 2513 was from a commercially reloaded copy I get from a local guy, the 2750 was from factory new Black Hills Mk 262
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Man thats weird, this is the BHs thats running 2650 over my magnetospeed out of a 7twist WOA 20"
http://www.midwayusa.com/product/114847/black-hills-remanufactured-ammunition-223-remington-77-grain-sierra-matchking-hollow-point-boat-tail-box-of-50
This barrel is very accurate but I dont understand how 16" barrels are getting 100fps faster than me.
He may have an tight bore. Button rifled bores can vary a bit in diameter. And it makes a BIG difference in pressure and velocity.
We've seen this in 30 cal barrels that have been pin guaged... then run the bullets and powder.... The tight bore's powder charge had to be backed down a significant amount to get the pressure safe.
guitarist1993
11-27-13, 15:18
The BH I'm running is the factory new white box, their 'seconds'. I didn't chrono the batch I shot today, but I did make sure to check for any signs of over pressure. I couldn't find any marks that would indicate an issue.
I think we had some 77s moving at 2900 fps on Saturday. This was out of the Rem 700 5R using ammo that's too hot for Gas gun use. I'm waiting for Pappabear to send me the chrono notes.
Yep, we averaged 2889, so I'm sure some were over 3K on a few. 2889 is primer popper in a gas gun. Our H322 precision load with a 16 inch bergara barrel produced :
69SMK 2697 fps
77SMK 2527 fps
Mark has another load with XBR that doesn't pop primers that is 100 fps faster , so you should be able to get 2627 fps with 77's. We didn't chrono it last Saturday, but we have in the past.
With shooting 69gr SMK's in my ARs both 16" Carbines I try for abouy 2700 fps , I've pushed them to the max load with Varget an popped primers. now I load 1gr under max . Never shot 77 gr so I can't say with 75 gr 2600 is pushing it in my AR's.
Yep, we averaged 2889, so I'm sure some were over 3K on a few. 2889 is primer popper in a gas gun. Our H322 precision load with a 16 inch bergara barrel produced :
69SMK 2697 fps
77SMK 2527 fps
Mark has another load with XBR that doesn't pop primers that is 100 fps faster , so you should be able to get 2627 fps with 77's. We didn't chrono it last Saturday, but we have in the past.
PB and Mark,
Is the 69 SMK at 2697 fps with 22.9 gr. of H322 or are you running more powder than that?
I'm trying to achieve similar speed with the 69 SMK in a 14.5" polygonal barrel. Perhaps I will need the XBR rather than H322, but consistency is more important than speed for me. Sierra does not list a load with H322 for the 69 SMK in the AR rifle section.
Thanks.
Yeah. The 22.9 is the only 69 gr combo we've tried. It's hodgdon's max .223 charge. You could likely go over that charge if you work up. I've gone over max published on the 77 and it didn't show any swipes or primer pops.
H322 burns on the faster side so work it up incrementally.
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