Shorty ARs

[alan]

In your experience, what hardware changes have had the biggest effect on taming gas and keeping reliability high for builds between 10.5 and 12.5"?

 

[KonoctisWigwam]

300 blackout has some 1:5 twist barrels, and those can go shorter, I have a Faxon that is 7.5" in length. I like 12" to be safe, and that goes for 6.5 Grendel also, which doesn't shoot subsonic.

12" is where it's at for 8.6 blackout, shooting 210 grain TTSX bullets, that will act like a blender after it flowers open.