Suppressed supersonic without adjustable gas?

[messer454]

So if I have a 16" .450 AR upper that is functioning properly and ejecting at about 4 o'clock with a standard carbine and buffer spring....Is there a combination of buffer (H3?) and extra power spring that is likely to cycle a standard supersonic round without an adjustable gas block through a suppressor?

I can't seem to find the answer. My buddy is trying to accomplish this on his .308 and got me thinking if someone here has done it on a .450. I assumed I would need adjustable gas. However quickly switching back and forth is not that important to me.

Thanks

[Buckeye45]

I think you are looking at this backwards. If you are running fine unsuppressed then it will actually have more gas pressure when suppressor is installed and therefore cycle “better”. It may run a little fast with the increase due to the can, but maybe will be ok.
I run an adjustable gas block choked down just to tame everything down. I can screw on my can and shoot supersonic ammo and there is no appreciable difference in function. I think the straight wall design is more forgiving in these situations.
Really there are so many variables that there is no way to predict what you will need until you just try it.

[plant_one]

quite likely its going to be at least somewhat overgassed... how much is a story for trial and error unfortunatly.


if you had a 20" carbine gas i'd say yes 100% need AGB... we just put one on my buddy's so he could put his can on it now that he's out of NFA jail. i cant wait to shoot it.

[Bmt85]

I agree with Buckeye and plant_one, try it and see.

A couple big things that will effect this is your gas system length, port size, and if your running handloads.

Carbine buffer weights are usually: Standard (3.0oz), H1 (3.8oz), H2 (4.6oz), and H3 (5.4oz). After that you have at least one option, and that's a Slash's XH buffer (8.5oz)
With heavy springs, I personally don't like them, especially for something like the 450B.