In this Tech Tip by Brownells we’ll be looking
at gas block alignment pins. As we’ve said in the past, the most commonly
encountered failures in the AR platform are cycling issues. And the most common culprit
on fresh builds is misalignment between the barrel gas port and gas block. Until now we’ve
never had a surefire way to get correct alignment every time.
These gas block alignment pins are a quick and easy, low tech solution to ensure proper
indexing of your gas block. So let’s check out how it works on this nearly completed
build. First we’ll go ahead and grab our alignment pin set and check for the correct fit in the
gas port in the barrel. Multiple pin sizes are necessary due variations from manufactures
and gas system lengths. Once we find a pin that fits but yet still moves freely we can
break the pin off from the base tab. Now we can slide the gas block assembly onto the
barrel. Then flip the upper upside down to allow the pin in the gas port to drop down
and align with the gas block. With everything aligned, secure the gas block into place.
Our last step will be to remove the alignment pin.
To do so, we’ll flip the upper upright, allowing the pin to drop back down into the barrel.
Then grab the correct caliber cleaning rod and insert it into barrel from breach to muzzle.
This will break the alignment pin in two allowing it to drop free and the first half to be pushed
out. Then retract the rod past the gas port allowing the second half drop into the bore
and be pushed out. We must stress the importance of removing and verifying both pin halves
have been removed to avoid any potential damage to your rifle. With the gas block torqued
down and both pin halves located we now have a properly aligned gas block.
All that being said, if you’re in a pinch and don’t have a set of gas block alignment
pins on hand here’s another easy way to get your alignment close. Grab a straight edge
and a lead pencil and make a mark down the center front of the gas block, being sure
to get it as centered as possible. Next, we’ll again use our pencil and straight edge and
make our mark on the barrel centering off the gas port. Once marked, we’ll slip on our
gas block assembly and align our 2 marks. Lastly, we can torque down our set screws
and head to the range for a test fire to insure everything is properly aligned. Unfortunately,
unlike the gas block alignment pins, this isn’t a surefire way to ensure alignment so
it may take a bit of trial and error to get everything perfectly indexed.
Hopefully this will get you up and running on your next build. Thanks for watching and
be sure to visit Brownells.com today to purchase a set alignment pins along with everything
else you need to complete your next AR project, all backed by our 100% unconditional, forever