Adjustable gas block seizes up

Snap! I should have gotten this one instead for a few more dollars.

Permatex 77134 Nickel Anti-Seize Lubricant, 0.5 oz Tube https://a.co/d/dbr7xaQ

Oh well. Anything at all will do better than before. Will see about that. It is the gas particles that manages to get into the threads that we need to worry about. Hopefully the metal surfaces cool it down.

In this particular gas block, the main screw is pretty long, going from the front of the block to the gas orifice near the rear of the block. The original set screw is about 0.7" long. I have replaced it with a 0.875" stainless steel socket head screw. I most certainly don't need all those threads just to give it more chance to get stuck. I may file some of those threads away. But I leave at least 0.3" or so there. If the threads fail, the screw could become a projectile under pressure.

I have been using gunzilla to deal with carbon build up. It works slightly better than all the other method I have tried. I have thought of, but haven't tried, motor oil. Interesting point about the temperature. I may try it with the parts warmed up with propane torch. In this case of stuck gas block, I wouldn't think it would have helped. The screw was stuck by corrosion on the black oxide screw, probably due to high temperature, other than carbon deposits per se.

Thanks for the info, Unclenick.

-TL

Sent from my SM-N960U using Tapatalk
 
Wow! Even higher than my stuff. I've had mine for decades, though. I wouldn't be surprised if whatever they use to make it into a paste is something newer.

The oxidation of the screw is a little unexpected, as propellant residue doesn't normally rust regular barrel steel. I wonder if the carbon isn't attracting moisture.

Carbon gets harder as it sits. Hummer70 points out that if you decap a case immediately after firing the cartridge, the residue just about falls out of the primer pocket. Let it cool and harden a bit and it gets crusty and hard. Let it keep sitting and it gets really hard. So, the sooner you get a drop of Gunzilla on it, the better.
 
I agree. It is almost like the carbon deposit absorbs water in the air and turns itself into cement.

I can't really tell whether it was rust on the screw. It was rough looking stuff. Could well be carbon. The gas block was a $20 cheap part. The screw is no better than the one sold for cheap at hardware store. The anti seize at least will seal the voids in the threads to keep carbon particles from entering, I hope.

So far I feel good about the fix. But still it wouldn't hurt to exercise the screw whenever possible.

-TL



Sent from my SM-N960U using Tapatalk
 
You must log in or register to reply here.
Back
Top