7.5 SBR excessive gas blowback

[Navy Gunner]

I have a 7.5 inch AR, running a allen gunworks linear brake, PRI gas buster, and H3 buffer. Cycles well, but every once and a while i'll get some gas blow back, almost like a bit of sand in my face. Anything else I can to cut down on the gas? changing the brake to a vortex?

Thanks

 

[Hitzy]

Are your fired cases coming out black?

 

[jawsman]

What powder are you using? It was suggested to me when I got my shorty to move to a much faster powder so the amount of unburnt powder would be dramatically reduced. I switched to H4198 from BLC-2 and it was night and day difference.

My $0.02.....

 

[Navy Gunner]

What powder are you using? It was suggested to me when I got my shorty to move to a much faster powder so the amount of unburnt powder would be dramatically reduced. I switched to H4198 from BLC-2 and it was night and day difference.

My $0.02.....

The reloads are WC 735. I may try factory loaded to see if that makes a difference.

 

[Navy Gunner]

Are your fired cases coming out black?

Not that I noticed.