Home Forums Hunting & Shooting AR and Tactical Rifles New Law enforcement build

Definitely there are options for any barrel configuration when you are not limited to the off the shelf barrels. I have cranked our barrels for different purposes, from match rifles 0.936 gas blocks with +2 gas system to finish at 26 to lightweight carbine gas system. Chambered a few SPR 18 inch with rifle gas Even 18 inch 6.5CM to 26 in the 308 AR platform. Of course each takes a different approach to make sure they are reliable and safe.

Chamber wise, I have reamers ranging from zero freebores to .170 for different purposes, and with different neck ODs. For Butch's project I would most likely use a 0.025 freebore, comparable to a CLE. That's what I use on my MK12 SPRs Mod 0, and also for my friends. These are all running AEM5s cans. They shoot real well, one guy aced the pop up qual just screwing around. Took them to 750 MK262s, no problem. I figure with Butch's project they can shoot the 69s through 77s match ammo and they should be good.

Have to admit, I have not done as many short barrels ones as I do full blown NM competition 20 inch service rifle barrels.

Here is one I did for a butter bar, 16 inch with 15 inch SLR handguard. Configuration was suggested by his Dad who was an ODA-x officer. It was a pain to modify the handguard and the bottom of the flip up clamp type BUIS. I used a zero freebore on this one as it will be feeding it with M855 A1s, occasional M855s till the Army quit issuing them. The barrel has 1 inch inside the handguard leading to the gas block.

As far gas block loosening, even on clamp type is no issue. We learned a lot when shooting A2s in competition. We drilled and tapped the pin holes in the A2 A frame so we can adjust/zero the rifle for no wind with the rear sight on MZ. To secure the front assembly we use the opposing set screws to align and clamp, them drip 290 Locktite. That green Locktite will hold the alignment and can take the heat. It can survive in a rattle battle multiple strings in practice. That is dumping 30 plus rounds on E silhouette at 600 yarda in 50 seconds. 28 plus hits in 50 seconds is a lot of fun.

Back to Butch,'s build, I am not worried about it going single shot due to loosening gas block. Rebarreling rifles with 290 Locktited gas blocks takes heat to loosen them.