View Full Version : AR-15 Front Sight / Gas Block Alignment

June 29, 2008, 11:08 AM
My gas block on my new A2 20" upper looks to be a hair bit off-alignment.

I shot the rifle for the first time yesterday, and it is definitely off-alignment. Looking from perspective of the rear sight, the front sight on-top of the gas block isn't quite 12 o'clock straight up. Closer to about 11:52 or so.

As a result, on a little 25 meter sight in target, I was about 5" off to the right.

I had to adjust my windage at the rear sight considerably to the left to compensate for the misaligned front sight. If it were only 3-4 clicks, that'd be fine, but I'm over at least a dozen clicks.

The gas block appears to be pinned, not screwed. I'd guess that most of what holds it in place is lock-tite or some similar strong gripping compound, and those pins.

How do I fix this? Is the do-able by me, or should I just have a gunsmith do it? Any negative impact to the gas tube?

This is a Del-Ton A2 configuration heavy barreled upper.

Also... what's a good place to get the sight elevation tool for the front sight?

June 29, 2008, 11:28 AM
Barrel is not torqued/aligned correctly, thats a generally known problem from the "lesser" manufacturers. Bushmasters and DPMS were notorious for that

Send it back.

WildeasysolutionAlaska TM

June 29, 2008, 02:05 PM

Thanks for the response... man, I hate warranties and post offices. Put the two together and they make a very, very good Redhawk Repellant. :p

Can this be fixed by a local gunsmith for reasonably cheap? What's a fair price to check the torque and alignment of the barrel into the receiver and straighten the front post/gas block?

June 29, 2008, 09:31 PM
Removing/installing the front sight gas block seems pretty staight foward. Here are several videos on working on AR's from Brownell's. They're also the best firearm parts and tool supplier that I know of IMHO.


As far as having a gunsmith fix it, that decision would probably lie in your ability to effectively work with tools. Weigh the satisfaction of learning your rifle and fixing it yourself versus time and money.

June 30, 2008, 10:15 AM
If the barrel nut is overtorqued, then you'll just need to remove the barrel and replace the probably-bent indexing pin and correctly torque the barrel nut. It's really simple to do, assuming you have the proper tools. About all you need is an action block that fits in a vise, a punch, barrel nut wrench, and torque wrench. A little more tedious than adjusting a Remington trigger, but, believe me, it ain't rocket science!