Tech Tip: Gas System Alignment

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 satisfaction, guarantee.

Channel: Brownells, Inc.

Views: 83,828

Rating: 4.9273276 out of 5

Keywords: 3932341232001, gas systems, Brownells, AR-15, gas block alignment, gunsmithing, AR15, alignment pins, tech tip, brownells.com

Id: cwmUewVwHdM

Length: 3min 3sec (183 seconds)

Published: Mon Dec 15 2014