Blow back with different barrel lengths.

[ace4059]

I was wondering what is the best setup with a suppressor. What is considered the best gas system best barrel length for reduced blow back?

I know that there is a substantial increase in blow black when using a suppressor but it seems that some of my guns are worse than others. My 11.5" BCM upper, 16" BCM mid length and 20" rifle are tolerable but when using my BCM 14.5" mid length the gas blow back is more pronounced and is bothersome. I thought the mid lengths would have less blow back than the carbine length gas system. I dont mind the dirty uppers, lowers, and magazines when using a suppressor, its just the extreme amount of gas in my face with the 14.5". All others are tolerable with the gas in my face.

[jonconsiglio]

I'm no expert on this stuff, I just worked with what I had. But, one of the guns I owned with very little blow back was a 10.5" LMT with a Vltor A5. My SR15 had almost none, but that too had the Vltor A5 at the time.

[ace4059]

Does anyone else know the optimum barrel length and gas setup (DI) for minimized gas blow back?

[markm]

There is no one right set up. If blow back is your goal, get an AAC Mini4. In other words, get a can with the least amount of back pressure.

[saddlerocker]

It's more about gas port size than anything. You could have 2 14.5" middys and get different results.

[markm]

It's more about gas port size than anything.

I have not found this to be true. I dialed my Syrac down to where the gun would only operate with the can on, and I was still getting a face full.

[Eurodriver]

I have not found this to be true. I dialed my Syrac down to where the gun would only operate with the can on, and I was still getting a face full.

Seconded.

It cycles more smoothly, ejects brass at 5:00 instead of 2:00 (oooOOOOooo) and overall feels better, but when firing a quick string you still get gas in your face.