AR SBR build

[SloppyJ]

I think a 12" 6arc would be a sweet setup. The gas system might get a little wonky if you're suppressing it though.

 

[RockAndSage]

I think a 12" 6arc would be a sweet setup. The gas system might get a little wonky if you're suppressing it though.

I just won't build an AR anymore without an adjustable gas system - there are so many variables with ammo pressure, port size, port distance from chamber and muzzle, recoil spring power, buffer weight, that people just chase their tails through all sorts of "tuning" part swaps. Solve all that with an adjustable gas system in one trip to the range, and be done with it.

 

[FredBear86]

Following. Keep the suggestions coming

 

[Chris_in_Idaho]

I just won't build an AR anymore without an adjustable gas system - there are so many variables with ammo pressure, port size, port distance from chamber and muzzle, recoil spring power, buffer weight, that people just chase their tails through all sorts of "tuning" part swaps. Solve all that with an adjustable gas system in one trip to the range, and be done with it.

Which system is your go-to?

 

[tradman]

I've got a 8in 300blkout. I've taken elk and deer with it using the 110gr barnes blacktips, suppressed of course.

 

[texag10]

Which system is your go-to?

Superlative arms has done well by me, the venting at the gas block seems to cut down on gas coming out of the ejection port. I have them on 2 ARs.

 

[fwafwow]

Thanks to the OP. This thread has me reconsidering my SBR setup, which is currently for home defense. I may put one of my extra scopes on mine, and maybe switch my red dot to an offset.

 

[justinspicher]

I just won't build an AR anymore without an adjustable gas system - there are so many variables with ammo pressure, port size, port distance from chamber and muzzle, recoil spring power, buffer weight, that people just chase their tails through all sorts of "tuning" part swaps. Solve all that with an adjustable gas system in one trip to the range, and be done with it.

I’ve never had a problem with non adjustable gas systems. Mine seem to shoot whatever ammo I feed it just fine.

I really feel that folks that are chasing tuning on an AR are trying to make that system into something that it isn’t and was never designed to do.

Just my thoughts.

 

[BRTreedogs]

Thanks to the OP. This thread has me reconsidering my SBR setup, which is currently for home defense. I may put one of my extra scopes on mine, go ahead and fill out and file the Form 20 (I usually only travel to one state that's a possible destination) and maybe switch my red dot to an offset.

Or just build another complete upper to swap on for hunting.
Just sayin

 

[fwafwow]

Or just build another complete upper to swap on for hunting.
Just sayin

I like the thought. But that shorter barrel seems like a great setup, and I will probably try it again in my home state.

I thought about filling out a Form 20 for the place I'm most likely to go out of state, but the way I'm reading the form and instructions, you sort of have to know when and where you are going - not that I can complete the form and keep it in reserve if and when I go there.

 

[BRTreedogs]

I like the thought. But that shorter barrel seems like a great setup, and I will probably try it again in my home state.

I thought about filling out a Form 20 for the place I'm most likely to go out of state, but the way I'm reading the form and instructions, you sort of have to know when and where you are going - not that I can complete the form and keep it in reserve if and when I go there.

The lower is the sbr, you can swap whatever barrel length upper you want back and forth.

So you can have 2 short barrel uppers with different optics.

 

[fwafwow]

The lower is the sbr, you can swap whatever barrel length upper you want back and forth.

So you can have 2 short barrel uppers with different optics.

I know that and do have multiple uppers for the SBR. But I had in my mind that I could just use my SBR, fill out and file a Form 20, then just wait for the OK and then travel to that destination if and when I feel like it. Or not.

Now I'm wading down the path of switching my currrent setup from red dot only to scope plus offset red dot.

 

[RockAndSage]

Which system is your go-to?

For lightweight or more refined builds, the Superlative Arms adjustable blocks, in Titanium. For rugged, hard-use builds that I can just throw any ammo in at any time, I'm partial to RifleSpeed, mostly because of the ease of adjustment on the fly. Heavier than Superlatives, but good quality. Especially for lightweight builds, I have also been partial to the gas-adjustable BCG from 2A Armament, which adjusts the gas flow right where the gas key opens up into the carrier's internal piston chamber. They're no longer made, however, after having been bought out by Nemo Arms. I did contact Nemo awhile back, and they said they expected to make their own updated version of that BCG, but I haven't seen anything yet. IIRC there's another company making their version of it - Bootleg, I think - but I don't have any experience with it.

 

[RockAndSage]

I’ve never had a problem with non adjustable gas systems. Mine seem to shoot whatever ammo I feed it just fine.

I really feel that folks that are chasing tuning on an AR are trying to make that system into something that it isn’t and was never designed to do.

Just my thoughts.

As a general rule, I actually don't disagree with you on this. Most people are best off making sure all their parts are of weights, dimensions, and specs as close to milspec as possible.

But at the same time, anything that's not a rifle-length gas system on a 20" barrel running 55gr 5.56 NATO spec ammo is absolutely not what was the system was designed to do.

Deviate from that, and you need to start tuning. Not saying this is the case with your personal builds, but my experience has been that most guns guys build themselves that actually are reliable tend to be overgassed to varying degrees. And that's fine for a hard-use gun, as long as the parts are robust and you don't need extreme accuracy.

My approach to tuning is a bit like tuning your handloading for a given gun - if I'm building lightweight, or precision, or a non-5.56 cartridge, all those moving parts and the applied energy of the gas needs to come together in harmony to make sure the BCG is moving backward and forward with the right velocity and momentum to reliably extract, eject, strip a round off a full mag, and chamber it reliably. The more you get away from Milspec on anything, the more accounting for all these variables matters. Having an adjustable gas system is just about the easiest way to make sure that BCG is in the right window of performance.