The Firing Line Forums - View Single Post - AR-15 Front Sight / Gas Block Alignment

azredhawk44 · 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, 11:08 AM	#1
azredhawk44 Junior member Join Date: September 28, 2005 Location: Mesa, AZ Posts: 6,465	AR-15 Front Sight / Gas Block Alignment 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?