Best Suppressed SBR Ever????

[Eurodriver]

I still occasionally hear horror stories about gas blocks carbon locking. I actually ran one for a bit on a 14.5. Didn't really care for it. I know a 10.3 is a whole different beast but I prefer the rock solid reliability of a normal gas block.

Amen.

[BufordTJustice]

I still occasionally hear horror stories about gas blocks carbon locking. I actually ran one for a bit on a 14.5. Didn't really care for it. I know a 10.3 is a whole different beast but I prefer the rock solid reliability of a normal gas block. I guess my first mistake was trying to fix too many variables at once. So is the best answer for me to switch back to the Geissele? Now that I have a properly ported barrel plus the way my previous setup acted (minus ejection), going back to the Super 42 should be perfect then correct?

Having shot tons of suppressed with my AGB, without a single issue, i think it's important to be very specific when it comes to AGBs. I use SLR Ti set screw blocks. Not one single issue. On my duty upper, on my wife's 18" rifle gas, on my 11.5" suppressed shorty. I have many dozens of buddies who have used (and still use) the steel model for years without issue on their suppressed and non suppressed rigs.

However, and i should note, that saying "i tried an adjustable gas block" and applying it to all adjustable gas blocks is tantamount to stating "i shot a gun" and now being under the impression that this knowledge is compete and applies to all guns. Not to mention, that the gas block is the easiest thing to screw up during install.

Nothing about the carbine action system is optimized. Though the Geissele system is what i would run if i were forced to attempt to pick up a turd from the clean end, it's not ideal.

The A5 provides timing and system cycle speed advantages that a Carbine system cannot attain.

Right now, you seem to have a gas drive issue. Fixing THAT is the best way to go.

Black River Tactical has a std low pro gas block that is designed to accept captured, threaded gas port reduction inserts. If you have a concern about the reliability of an SLR gas block, get a BRT. But the gas drive issue cannot be properly addressed even with an A5H4 buffer.

Lastly, adjustable gas blocks are not designed to be toggled, like a gear shift. They are designed to be adjusted like an adjustable trigger and then left alone. However, despite that, I've never had an issue adjusting my SLR for setup changes.

Sent from my SPH-L720T using Tapatalk

[OldState]

I was following this thread for a few years and even bought a 6920 as a base gun for a SBR build to be run suppressed and unsurpressed before the 2016 election. Original plan was to have the barrel shortened and a adjustable GB put on...probably pinned. Then add an LMT enhanced carrier and possibly the A5 system.

For numerous reasons the my project was mothballed. Fast forward to now with the new ATF comments on pistol braces along with the release of several new designs I’m considering a BCM pistol with an 11.5” upper or just the lower and proceeding with modifiing the Colt upper I have. Possibly SBRing the Colt lower later.

My question is, since there hasn’t been a post here in a year, is the secret sauce still valid? Did I miss a new product on the market?

Thanks!

[nightchief]

I think "the science" is certainly valid. I've been tuning an 11.5 SBR, to run suppressed more often than unsuppressed. This thread and some private messages with other members really led me down a good path to get an optimum running system.

I used a 11.5 Sionics RGP barrel and reduced the gas port further with a Black River Tactical microtune gas block at 0.67; an LMT e-carrier; and A5 RE with A5H1 buffer and green spring. Using SF 556-212 suppressor, its running very smoothly and the gas to the face has been eliminated.

Unsuprressed, it was struggling to lock back on an empty magazine with an A5H2 buffer, but is reliably locking back with A5H1 buffer. I tested it both suppressed and unsuppressed a couple of days ago when the temp was about 28 degrees and it ran very well. The recoil impulse is slightly greater suppressed with the A5H1, but I would rather have the reliability unsuppressed, so I settled on the A5H1.

In comparison, the RGP barrel with .070 gas port runs ok, but there is noticeable gas to the face. It also requires a carbine RE with H3/blue spring or A5 and A5H3 or H4 with green spring.

NC

[BufordTJustice]

I think "the science" is certainly valid. I've been tuning an 11.5 SBR, to run suppressed more often than unsuppressed. This thread and some private messages with other members really led me down a good path to get an optimum running system.

I used a 11.5 Sionics RGP barrel and reduced the gas port further with a Black River Tactical microtune gas block at 0.67; an LMT e-carrier; and A5 RE with A5H1 buffer and green spring. Using SF 556-212 suppressor, its running very smoothly and the gas to the face has been eliminated.

Unsuprressed, it was struggling to lock back on an empty magazine with an A5H2 buffer, but is reliably locking back with A5H1 buffer. I tested it both suppressed and unsuppressed a couple of days ago when the temp was about 28 degrees and it ran very well. The recoil impulse is slightly greater suppressed with the A5H1, but I would rather have the reliability unsuppressed, so I settled on the A5H1.

In comparison, the RGP barrel with .070 gas port runs ok, but there is noticeable gas to the face. It also requires a carbine RE with H3/blue spring or A5 and A5H3 or H4 with green spring.

NC

I think your experience just verifies that most barrels are WAY overgassed for suppressed use. And, even reduced gas barrels can still be gassed higher than is optimal even for mixed suppressed use.

Glad you got your rig running right!

Pics?

[nightchief]

I think your experience just verifies that most barrels are WAY overgassed for suppressed use. And, even reduced gas barrels can still be gassed higher than is optimal even for mixed suppressed use.

Glad you got your rig running right!

Pics?

I agree on the overgassing. BRT gas block is a slick component for mitigating the issue.

I'll have to get some "action" pics next time out.

[BufordTJustice]

I agree on the overgassing. BRT gas block is a slick component for mitigating the issue.

I'll have to get some "action" pics next time out.

Yep. The block or the new gas tube are great ways to adjust gas flow.

If you don't get a pic of your rig thrown recklessly into a snow bank then the internet won't think you're cool enough. Lol

[nightchief]

Yep. The block or the new gas tube are great ways to adjust gas flow.

If you don't get a pic of your rig thrown recklessly into a snow bank then the internet won't think you're cool enough. Lol

I'd be in on that if we ever get any snow here! We get snow her in Texas about as often as you do in Florida...

Might have to settle for a pic in some tall grass or in a ant hill

[BufordTJustice]

I'd be in on that if we ever get any snow here! We get snow her in Texas about as often as you do in Florida...

Might have to settle for a pic in some tall grass or in a ant hill

Right on. I was born in the DFW area. Lived there as a child. I miss the Blue Bonnet fields.

[nightchief]

Ok, shooting buddy apparently took a pic of me shooting the aforementioned upper after it "warmed up" a bit...

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