Looking to use a Geissele mk16 rail in my upcoming 14.5" build and would like to run an adjustable gas block with a JP silent capture buffer spring system to get the build shooting as flat and smooth as possible. Given the issue of the mk16 bending when being dropped and hitting the gas block, I'm looking for as small of a block as possible. My top choice is the Superlative Arms adjustable gas block, but I wanted to see if anyone had any experience running it (clamp on or set screw) with an mk16 rail. I like how Superlative Arms off-gases the excess gas out the front, I'm just worried about clearance issues with how small the inner diameter of the mk16 is. Curious to see what other users have had success/failure with.
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1.25" according to the "official" mk16 thread on arfcom. Geissele website does not list.
Not much clearance. The .625 set screw SA gasblock is 1.259 tall, I believe that is the smallest they make. Pretty thin barrel to get there.
I have the MK14 rail and the Superlative Arms gas block. It does fit but it's tighter than I would like. The issue isn't the portion of the gas block that goes around the barrel, there is plenty of room for that and the ID of the MK14 is 1.27". Where it is tight is in the top portion of the handguard where the gas tube goes. That is where it is tight and may be an issue for you. I think the SA gas blocks are a little fatter in the upper area where the gas tube goes than other gas blocks. This is based on test fitting of the MK14 rail only as I haven't built the upper for it yet.
I think the bleed off feature is more for SBR/suppressor users where the gas system can be over gassed. If you're building a 14.5" without a suppressor you'll be fine with a regular adjustable gas block like that from SLR Rifleworks. I have both companies gas blocks and love them both. They are both great.
I think the bleed off feature is more for SBR/suppressor users where the gas system can be over gassed. If you're building a 14.5" without a suppressor you'll be fine with a regular adjustable gas block like that from SLR Rifleworks. I have both companies gas blocks and love them both. They are both great.
And btw, with proper recoil management techniques you'll have a flat shooting rifle without things like adjustable gas blocks and buffer springs and brakes. It just takes practice of proper shooting techniques. 
Could always go with an adjustable carrier if your adjustable gas block is a no go. Bootleg makes one.
Maybe.
www.seekinsprecision.com
Smallest I have seen, I have two now.
Low Profile Adjustable Gas Block
Low Profile Adjustable Gas Block The Seekins Precision Low Profile Adjustable Gas Block lets you fine-tune your rifle's gas system for smoother cycling and operation. Regulating the amount of gas used to cycle the action, or "tuning" the gas, is critical
www.seekinsprecision.com
Smallest I have seen, I have two now.
Maybe.
Low Profile Adjustable Gas Block
Low Profile Adjustable Gas Block The Seekins Precision Low Profile Adjustable Gas Block lets you fine-tune your rifle's gas system for smoother cycling and operation. Regulating the amount of gas used to cycle the action, or "tuning" the gas, is critical
Smallest I have seen, I have two now.
How has the side adjustment been for you lining up with handguard? I've wanted to try one out, should just buy a damn new rifle from them. Solid company
I had to get a hex key with the end that has undercuts like a ball drive.
That way I didn't have to mod the rail any at all.
Only drawback is the new hex driver is too long to fit into pistol grip storage.
Function has been perfect, 1 turn out for suppressed and three tuns out for unsuppresd, repeatable.
Compleatly smoothed out my grossly overgassed upper that was jumping and ripping up brass.
That way I didn't have to mod the rail any at all.
Only drawback is the new hex driver is too long to fit into pistol grip storage.
Function has been perfect, 1 turn out for suppressed and three tuns out for unsuppresd, repeatable.
Compleatly smoothed out my grossly overgassed upper that was jumping and ripping up brass.
Sure, and with good driving techniques I can drive a truck faster than your sports car. That doesn't make it better.And btw, with proper recoil management techniques you'll have a flat shooting rifle without things like adjustable gas blocks and buffer springs and brakes. It just takes practice of proper shooting techniques.
A properly tuned rifle will always shoot flatter than something overgassed, and it's easier to do it with. There's no reason to tell other people not to do it right.
With that said, the bleed off thing in the Superlative blocks is just marketing. Get the Seekins block and be done with it.
I use a .750 superlative under a mk14 and there is plenty of clearance. I just tried moving the barrel to get the gas block to touch the handguard and i couldn't do it. Not sure if the mk16 has the same ID but if it does you should be ok.
I used the Superlative Arms adjustable gas block on two 14.5 builds. One used the .625 and the other .750, both rifles have the MK14 rail.
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