Proactive measures to prevent gas leaks

[Steve in Allentown PA]

I spent a decade behind an M16 buttstock courtesy of Uncle Sugar so while I know which end is the dangerous one and I can field strip it, I do not have an intimate knowledge of its inner workings. To alleviate my ignorance in this area I've collected all the necessary bits and pieces to put together my first upper.

 

The gas block slips easily over the barrel boss. It is not a press fit. I'm looking for tried and true methods to prevent gas from leaking out from between these two parts.

 

Same question for the gas tube and the gas block.

[Nathanb]

Is your barrel dimpled? It will help keep the block aligned first and foremost. 
 

ive never paid a ton of attention to leaky blocks. As long as it runs. Adjustable seem to have this issue more often than not 

[StealthyBlagga]

The area under the gas block and around the gas tube will eventually accumulate firing residue that will reduce leakage somewhat, but sealing in these areas is unnecessary - the system was designed to accommodate some leakage and still function properly. Just shoot it and troubleshoot if you have a problem.

Edited August 29, 2021 by StealthyBlagga

[mpom]

The gas port is on top of the barrel, the set screws on the bottom pull the gas block down, which usually eliminates gas leakage from barrel/gas block interface.

A clamp on gas block self seals the gas port.

A bit of leakage between gas tube and gas block is normal and expected, as mentioned above.

Now some gas block use a cross pin to secure to barrel, just like the M16 you had, but you did not mention which gas block you have.

 

Mark

[Steve in Allentown PA]

It's an Aero Precision non-adjustable gas block with set screws going onto an AR Performance barrel that's been dimpled for the set screws.

 

I reached the same conclusion that the set screws will pull the gas block down into tight contact with the top of the barrel boss.

 

The fit between the block and the barrel is very close which allows the block to easily fit into place but it doesn't rattle around.  Guess I was making a mountain out of a mole hill.  Chalk it up to my total lack of experience in this arena.

 

Thanks everyone for your replies.

[TonytheTiger]

On particularly loose fitting gas blocks I've bedded them with blue loctite a few times. It fixed the excessive leaking. The leaking has never caused malfunctions, and eventually fixes itself as the carbon builds up, but I was just curious if it would work.

[K-Tex]

Clamp on should seal best over set screws, but can move away(not staying aligned) from the gas port if not properly tightened.   A gb that goes on snug will seal best regardless the style.