02-26-2014, 05:18 PM
LRRPF52 Wrote:I've seen gas blocks come loose. They were all set screw types. It will happen with guns that are run very hard on a high volume schedule, or are run in extreme cold on a high volume schedule.
The worst thing you can do is use an aluminum gas block with carbine-length gas systems. Even MLGS beautifully-machined 7075 T6 aluminum failed on a Mid Length Gas System AR15 that I tested in extreme cold for this very purpose.
On a Rifle Length Gas System, you can get away with aluminum because the port pressure is much lower, but I personally will never use Aluminum on the gas blocks.
If I use a set-screw attach, I prefer to also bed the gas block with Red Loc-tite, after a detailed and thorough gas system trouble-shoot, preferably with actual shooting.
So what are you using in your builds? Clamping or pin? Do you think you can get away with clamping on a duty gun?