View Full Version : Help with gas block pin

June 30, 2007, 20:00
I have an L1A1 that I shortened the barrel to 17". How do I get the gas block pin out so I can drill the gas port in the barrel larger? I tried a hammer and punch and using my large bench vise to press it out with a short piece of drill rod. The rod bent and the pin won't budge. Any suggestions?

June 30, 2007, 20:24
Push the other way. The pin is tapered. One way in, one way out. I can't remember which way it goes. The size difference is noticeable if the ends ore not buggered.

June 30, 2007, 20:33
I wondered if it was. My eyes not being what the used to be I couldn't tell. I'll measure it.

June 30, 2007, 20:52
Looking from the rear of the rifle the pin goes out right to left. So far I have ruined 4 good punches and the pin has not moved a bit.

Can I drill it through the front sight hole or will that make the hole in the gas block too large?

June 30, 2007, 21:56
Have you tried to shoot it, you may not need to open the port. You can drill the port with the gas block on. It is at a 45 degree angle through the hole where the gas adjust ring sits.

You can drill it. No bigger than the big end of the pin, no need to drill any larger than that. You will then have a straight hole and need a straight pin. Once you do this, you align the gas block so the sights line up. You will also need a suitable pin. Tools used for timing the barrel will align the gas block.

Maybe you could soak the pin in PB Blaster or Kroil and let it sit for the night? Kroil, over time, has done the trick on everything I've ever tried it on.

June 30, 2007, 22:46
Thanks, Kroil was my next trick. If/when I get the block off, do I need to enlarge the hole in it as well as the barrel? I will try shooting it before I drill the barrel.

July 01, 2007, 23:59
I shot the gun today without making any changes to the gas port. It measures .110". With S.A. surplus it wouldn't function at all even on the zero setting. PMC would function fully on 2.

Looks like I'll open it up to .116". Can I just drill the hole with the gas block on or do I need to remove it? It looks like I can just drill from the rear of the block down into the bore.

July 02, 2007, 00:02
Bore with gas block in place. No problems.


July 02, 2007, 01:13