Gas blocks

[Paul57R]

I'm looking for a low profile adjustable gas block. I see "set screw style" and "clamp on". Any pros or cons on ether? This will be going on my M&P AR 10, .750"

Thanks for your input

Paul

 

[Fourth Horseman]

My only input, having used both types, is that the set screw style are easier to get lined up properly, but if your barrel does not have the dimples already drilled into it then you'll need a jig so you can drill your own. The clamp on style blocks are very easy to put on, and they hold really tight and make a great gas seal, but you do want to take your time and do a good job with lining them up. I've used them on two different rifles now (my M&P 10 and a 6.8 SPC AR-15) and both times I just eyeballed it and they ended up being fine and working great.

Either way, when you get the gas block on be sure to put the bolt carrier group in and make sure the gas key lines up with the gas tube and nothing is binding up when the bolt carrier goes forward. If you get the gas block on in such a way that it's not lined up right, then it will cause some deflection at the end of the gas tube and the gas key can strike it when going home. As you push the bolt carrier group forward with your fingers you'll feel it if it hits the gas tube and isn't right.

 

[Paul57R]

Thanks Fourth Horseman for your opinion and tips. This is my first semi auto rifle so I'm sure there will be more questions to follow.

Paul

 

[Fourth Horseman]

Happy to help. One other suggestion, a drop of high temp thread locker (I use Rockset) on the gas block screws is a good idea. I like the added insurance that those screws aren't going to back out over time.