12.5” ar15 barrel, mid length gas, with a can, what gas block?

[Jgunner]

Ordered barrels from Sgt. of Arms 12.5 barrel, will be suppressed 100% of the time, mid length gas system.

Do i need an adjustable gas block?
Bcg will be full mass, unsure of buffer at this point, but probably a jp silent capture.

Gun will be ran f/a and semi.

 

[loveha]

When I built my 12.5 SBR I wanted reliability and did not go with an adjustable block. I went with a Lantac block. If I was going to do it again though, I might go with a pinned block. Mine is set screw, but not to concerned of it coming loose.

For buffer, just an H2, with a Hot White Sprinco Spring. The JP should work good, I would go with the H2 version.

Mine is ran with a Sandman S 100% of the time with zero issues.

 

[C_R_Slacker]

Adjustable. When you're dealing with non-standard parts, an adjustable gas block ensures you'll be able to make it run. I use superlative arms on all my ar's. Never had a problem.

 

[Jgunner]

Adjustable. When you're dealing with non-standard parts, an adjustable gas block ensures you'll be able to make it run. I use superlative arms on all my ar's. Never had a problem.

I was looking at those. Not sure how forward venting gas blocks work. Could you enlighten me? I want as little gas in the face as positive, was thinking about a slr adjustable but came across superlative as well and saw it was an interesting design.

 

[C_R_Slacker]

The idea is to vent excess gass out the front so it doesn't gas back through the chamber. How much of a difference it makes i can't really say, but i run my guns suppressed and with normal strings of fire, gas in the face is not an issue. If you were putting tons of rounds down range in a short period of time, doing mag dumps, etc then it may not help a ton. You can also run superlative gas blocks to restrict flow like other gas blocks if you choose to. I do this on a very over-gassed 308 because when suppressed i can't bleed enough off through the front.

How they work in a nutshell is that with the screw all the way in, the gas is off like any other adjustable gas block. Backing the screw out increases gas until the point that it's wide open. Keep backing it out beyond that, and it allows excess gas to escape through a port on the front of the block. There was a good video on YouTube i found once where someone made a model that explained it really well.

 

[Jgunner]

The idea is to vent excess gass out the front so it doesn't gas back through the chamber. How much of a difference it makes i can't really say, but i run my guns suppressed and with normal strings of fire, gas in the face is not an issue. If you were putting tons of rounds down range in a short period of time, doing mag dumps, etc then it may not help a ton. You can also run superlative gas blocks to restrict flow like other gas blocks if you choose to. I do this on a very over-gassed 308 because when suppressed i can't bleed enough off through the front.

How they work in a nutshell is that with the screw all the way in, the gas is off like any other adjustable gas block. Backing the screw out increases gas until the point that it's wide open. Keep backing it out beyond that, and it allows excess gas to escape through a port on the front of the block. There was a good video on YouTube i found once where someone made a model that explained it really well.

Thanks man. Ill look for that video. It might help keep things cleaner and less hot, since it is full auto. But mag dumps are not my intended use, it will happen occasionally.

 

[Jgunner]

Adjustable. When you're dealing with non-standard parts, an adjustable gas block ensures you'll be able to make it run. I use superlative arms on all my ar's. Never had a problem.

Thanks. Ill give em a shot!

 

[Texascbr]

I’ve been running Superlative Arms gas blocks on a several of my AR builds to include suppressed, lightweight, and full auto. I’ve been very happy with the results.

 

[MPDS13]

I would also suggest an adjustable gas block. I like the SLR ones they have worked well in several of my builds and been very reliable.

 

[Jgunner]

I would also suggest an adjustable gas block. I like the SLR ones they have worked well in several of my builds and been very reliable.

Thats what i have now. Been great. But sometimes there is something greater

 

[Stackon212]

I ran my 12.5 suppressed with a Bootleg adjustable BCG

 

[RC556]

Definitely look into getting the VLTOR A5 buffer setup. It will add about an inch to LOP but man is it worth it.

 

[Docsherm]

I have a Middy Rainier Arms 12.5 and I have a regular gas block. I have a regular BCG and a Vltor A5 Buffer system with a A1 buffer in it. It runs both suppressed and un-suppressed. I am not a fan of adjustable gas blocks.

 

[C_R_Slacker]

I have a Middy Rainier Arms 12.5 and I have a regular gas block. I have a regular BCG and a Vltor A5 Buffer system with a A1 buffer in it. It runs both suppressed and un-suppressed. I am not a fan of adjustable gas blocks.

If gas port is appropriately sized everything should run fine. But barrel makers don't necessarily know what other parts their customers will be using. A lot of people don't trust adjustable gas blocks. Has anyone done actual independent, long term testing of adjustable vs standard to see if they are in fact less reliable? It would be good to see real data, but I've never stumbled across it.

 

[Docsherm]

If gas port is appropriately sized everything should run fine. But barrel makers don't necessarily know what other parts their customers will be using. A lot of people don't trust adjustable gas blocks. Has anyone done actual independent, long term testing of adjustable vs standard to see if they are in fact less reliable? It would be good to see real data, but I've never stumbled across it.

I agree with you on this. Many Manufactures make all kinds of weird port sizes on barrels. I don't like the idea or adding a bunch of small parts to a area that is critical for operation. I will "tune" an AR with the buffer, Buffer weight, and BCG weight.

If that does not work, there is some type of issue with the rifle.

 

[Jgunner]

If gas port is appropriately sized everything should run fine. But barrel makers don't necessarily know what other parts their customers will be using. A lot of people don't trust adjustable gas blocks. Has anyone done actual independent, long term testing of adjustable vs standard to see if they are in fact less reliable? It would be good to see real data, but I've never stumbled across it.

Ive had screws back out of a couple. Then i went to the slr which works great, but doesn’t have a ton of adjustment. However, I wouldn’t want to be on the cusp of not functioning, as it gets dirty or hot it could malfunction. So i would rather be a little overgassed than undergassed.

I am not sure what port size they are, i have another 6-7 week wait from sgt of arms and tbox to finish them. I can ask him what port size, but he is on vacation and would rather not bother him. I also need to find out what contour they are . I know they are slightly smaller than gov profile, but not a pencil either.

Tbox Match Grade Pistol Length Barrel | Sgt of Arms

TBox are match-grade, hand-cut, profiled and chambered barrels. If you are looking for the cutting edge of accuracy without the high dollar price this is your answer. 416R Stainless Steel Button Rifling Hand Lapped .750 gas block Threaded and Crowned 1/2x28 for 223 and 5/8×24 for 300 blackout...

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Seems really cheap for a quality barrel.

 

[MSTN]

The SLR has worked well for me with my 12.5" Bartlein middie from Craddock Precision:

Also using the Vltor A5 recoil system and a full mass bolt carrier group. Both have proven to be effective systems on suppressed guns.

 

[Sincerd]

Kynshot, Tubbs flatware spring and vltor a5 extention tube. This with dramatically lower cycling speed. I think 30-40% IIRC. You can definitely feel the difference. Got mine with LMT EBCG and the gun doesn't move. Alot smoother than other guns I've shot on bleeding edge of reliability.

 

[FishinGuns]

These work well for dedicated suppressed:

Black River Tactical Store - Shop BRT

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