AR Sponsor
Posted: 4/5/2017 12:00:20 PM EDT
|
Im in the middle of putting together what I hope to be a precision AR, and am having difficulty determining the "best" way to attach the gas block. The barrel is a Compass Lake 18" Bartlein SPR profile (one dimple), and I intend to use a SLR Sentry 7 block.
I have access to a machine shop, so drilling the 2nd dimple and hole for a taper pin is no issue, but how much truth is there to the idea that a taper pin can induce a stress point in the bore? Would I be better off just going with two set screws alone, or a clamp on block and Rocksett? |
|
I'm no expert on the subject. Given the expectations for that barrel, I'd be inclined to avoid any major machining operations at this stage. I think that one set screw into the dimple and the second against the barrel should hold just fine. I'm assuming the gas block will be protected under a rail. It's not likely to be subjected to direct impacted.
FWIW: My Lilja M4 Navy Recce barrel came with a flat machined on the bottom for set screws. There were no dimples. The low profile gas block I used has two set screws in the bottom. I just tightened them against that flat. No thread locker or Rocksett or such. Your set screws are probably similar -- they are likely like mine, designed to be concave on the tip and flatten out when tightly screwed down. They should hold just fine. Of course, my experience is limited. |
|
I'd avoid machining anything. If you want a second dimple I'm pretty sure SLR sells a jig.
I have 3 of their blocks, 2 on larue barrels with 2 dimples(3 really) and 1 on a bcm with 1 dimple, all secured with rockset. They have all worked just fine. Worst case is it works loose and you need to use more rockset or locktite. |
AR Sponsor