If you read the sheet that comes with the gas block, IIRC 0-6 (don't quote me on that number) clicks out from fully closed is 'restricting' like a regular adjustable, and then everything past that is bleed off. Bleed off is recommended mainly because it's less likely the adjustment screw will get seized up with carbon, but to trouble shoot, I would start with it fully closed, and unscrew one click at a time until the bolt locks back.....then MAYBE one click more...
New AR build will not cycle open
- Thread starter Helka
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If you read the sheet that comes with the gas block, IIRC 0-6 (don't quote me on that number) clicks out from fully closed is 'restricting' like a regular adjustable, and then everything past that is bleed off. Bleed off is recommended mainly because it's less likely the adjustment screw will get seized up with carbon, but to trouble shoot, I would start with it fully closed, and unscrew one click at a time until the bolt locks back.....then MAYBE one click more...
My money is on this. Follow the SA instructions on how to tune your gas block.
I'm agreeing that it could be the way you have the gas block adjusted.
Also if you want to be sure the barrel's gas port isn't partially blocked by the gas block simply loosen off the gas block and slide it forward. The barrel will have carbon residue on it showing you exactly where the gas block's port was positioned. When reinstalling gas block adjust position accordingly if necessary.
Also if you want to be sure the barrel's gas port isn't partially blocked by the gas block simply loosen off the gas block and slide it forward. The barrel will have carbon residue on it showing you exactly where the gas block's port was positioned. When reinstalling gas block adjust position accordingly if necessary.
From the edge of the gas block to the gas port on the Superlative, is .200". Most gas ports are .275-.300" from the shoulder of the barrel. I could pull my MRA out but I'm lazy. You probably need .075-.100" space between the shoulder and gas block. You can always pop your gas block off and see where the carbon ring is, that should give you a good idea.
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In that case I'll also put money on the problem being how you have the gas block adjusted into the bleed off position.
The bleed off position is really only good for suppressor use to prevent the excessive gas pressures caused by the suppressor from going into the operating system. Unfortunately the bleed off position is a little redundant to us Canucks.
While I agree with you (and prefer using the 'restricting' mode), superlative recommends using bleed-off to prevent the adjustment screw from seizing up*. Having said that, once you get it set......often you don't ever have to change it (unless switching to a different barrel) so I guess it becomes a moot point.
*I've never actually used one in bleed-off mode, so for all I know the adjustment screw will seize up that way too
OP....by any chance do you have anything you can measure the gas port with? usually gas ports are drilled too big, but it's not impossible for them to be drilled too small.
Number drills work in a pinch (to gauge the size of the hole)
Number drills work in a pinch (to gauge the size of the hole)
From the edge of the gas block to the gas port on the Superlative, is .200". Most gas ports are .275-.300" from the shoulder of the barrel. I could pull my MRA out but I'm lazy. You probably need .075-.100" space between the shoulder and gas block. You can always pop your gas block off and see where the carbon ring is, that should give you a good idea.
Are you saying the center of the gas block hole is only .200" from the end, or .200" to the edge of the hole?
The hole in gas blocks is usually .100-.110" in diameter (similar diameter as ID of gas tube), and they should be ~.250" from end of block to center of hole.
Gas ports are supposed to be 7mm (.275") from center of hole to the journal shoulder.
Handguard caps (that I've measured) vary between .02-.03" (most are ~.025")
.075"-.100" gap between gas block and journal shoulder is WAY too much......
It’s .200 to the edge of the gas port.
Sounds like you guys are giving some good advice to the OP so, I won't add to it.
I have to ask, why are all of you guys running SA gas blocks if you aren't using the bleed off feature? Seams like there are better options if you aren't going to use the bleed off? Just honestly wondering.
I have to ask, why are all of you guys running SA gas blocks if you aren't using the bleed off feature? Seams like there are better options if you aren't going to use the bleed off? Just honestly wondering.
No, I meant other adjustable gas blocks. An adjustable gas block is a good idea for many applications imo. I just always see guys running SA that aren't even using the bleed off feature. It seams to me(correct me if I am wrong please)that the bleed off feature is the only real plus to the SA blocks. There are lighter/smaller/more durable blocks made by other companies(even ones with Inconel set screws for the ultimate resistance to erosion and heat damage). I just don't get the popularity/trend towards SA I guess?
My opinion (ymmv), a lot of the other gas block designs are either: a) not click adjustable, b) they don't have a locking mechanism to prevent the adjustment screw from moving once set, c) if they do have a locking screw, it's in an inconvenient location for quick adjustments
Superlative checks all those boxes, but also comes with a feature that I'd probably never use *shrugs*
Which blocks do you have in mind as 'next on the list'?
