LRRPF52 Wrote:Hi-power smiths have been doing it for years and years. Across a fleet of samples, it has proven to increase accuracy as well for some reason. Also helps prevent gas leakage. The other way is to approach it with a mechanical seal if you can.

Klem Wrote:Have they? First I've heard of it in 30 years ('and years').

My opinion is that you should use glue sparingly on AR's. If you are worried about a loose seal, get a tighter fitting block that taps on with a hammer or clamps. If it leaks slightly and the system still functions it's probably a blessing that you're not having to cope with that excess pressure at the receiver. If you think glue on blocks improves accuracy ('for some reason') then I have no counter argument for you here. That one is a non sequitur.

Sorry mate but I have to call it when I see it. I won't lose any sleep if you want to use glue on your block seal or advise others accordingly but the only glue on my guns are gas block screws and sometimes handguard screws.

jurassic Wrote:I use green loctite on the gas tubes, I haven't had a gas block leak around the barrel yet.

Klem Wrote:How do you know they have never leaked? And my point is, so what if they do?

If you decide your rifle needs a heavy buffer then surely you don't need every pound of (over) pressure available. I agree, it can't hurt to do this...until you decide to change barrels or blocks using a blowtorch and hammer. And I accept the idea that leaking gas does not sit right with the type of person that frequents these forums; precise personalities with expensive precision rigs.

I can also understand a situation where you need all the gas you can get to be reliable, for example a 300Blackout with carbine-length gas tube. However in other systems why maximize the gas return, only to then mitigate it with heavy buffers and expensive adjustable blocks?

lead chucker Wrote:I agree it cant hurt but i have built a number of ARs from 556, 300blkout and grendel and have never used loctite on a gas block. Just made sure they are aligned properly and go.

Klem Wrote:Have they? First I've heard of it in 30 years ('and years').

My opinion is that you should use glue sparingly on AR's. If you are worried about a loose seal, get a tighter fitting block that taps on with a hammer or clamps. If it leaks slightly and the system still functions it's probably a blessing that you're not having to cope with that excess pressure at the receiver. If you think glue on blocks improves accuracy ('for some reason') then I have no counter argument for you here. That one is a non sequitur.

Sorry mate but I have to call it when I see it. I won't lose any sleep if you want to use glue on your block seal or advise others accordingly but the only glue on my guns are gas block screws and sometimes handguard screws.

NugginFutz Wrote:Here is a group it shot over the weekend. The loctite obviously doesn't hurt accuracy.

NugginFutz Wrote:Ok - This is not to recant my stated feelings on the matter, but here is some real world data (with pictures!).

I recently assembled another table gun, a BHW 5.56 with a 22" Match Bull barrel. Ordinarily, I use clamp on style gas blocks, but due to this build's lightweight hand guard's configuration, I had to go with a lowpro setscrew gas block. I'd decided (this one time) to seal it with loctite because I'd heard good stuff about it here and on other forums. Didn't know what to expect, as I'd not done it before. Last night, I removed the hand guard to gain access to the barrel nut (checking other aspects of the build) and found this.

Gas blow by from gas tube - NOT gas block.


Removed block shows absence of gas blow by at gas port.

The gas was escaping at both ends of the gas block at the tube, which I'd merely pinned in place, without any sealant.

I reapplied it, as I'd originally done.


Reinstalled the block...


I removed the excess, and buffed off the gas residue I'd forgotten to remove while I had the block off.

So, does it work? I think this would seem to indicate it does. Does it help with accuracy? I can't really say. Next post shows a group from the barrel.