Adjusting Non-Adjustable Gas Block for 22LR Conversion Kit

[Dale's Dead Bug]

I'm going to be using a CMMG 22LR conversion kit a lot on my new 5.56 carbine. The rifle uses a low profile (non-adjustable) set screw gas block, and an M-lok handguard, so the gas block set screws are easily accessible. What might be the potential downside if, when using the conversion kit, I loosened the gas block set screws, slid the block forward about 1/4", and re-tightened the screws, thereby blocking the gas port and keeping unnecessary crud out of the block/tube/upper?

I found an archived thread on the subject of blocking gas ports for 22LR conversion kits, but it didn't address my idea.

[protohyp]

no downside...

depending on how many rounds you fire you'll probably still have to remove the gas block completely to clean the gas hole on the barrel

[dousan]

Why not buy an adjustable block? Like a slr one. They aren't that expensive

[mif_slim]

There shouldn't be any problems. I've shot my ar15 with conversion lots without and modification to my gb. Still shoots fine. Question is, how much will you be shooting to get leading in the gb and tubes...if a few thousand per year, I don't see why it'll be an issue...few hundred thousand... maybe an issue.

[Dale's Dead Bug]

no downside...

depending on how many rounds you fire you'll probably still have to remove the gas block completely to clean the gas hole on the barrel

Thankfully my handguard has open gaps on top, so getting at the port wouldn't be too difficult. Also figured I'd run a few rounds of .223 through it at the end of each session (with the block put back in its proper place of course).

Why not buy an adjustable block? Like a slr one. They aren't that expensive

This was an ultra-budget build. Cheapest versions of most parts. Also, it seems the adjustable blocks have the adjustment screw on the top of the forward face of the block, which would be trickier to adjust with my 12" handguard (though now that I think about it, I guess a long straight hex driver would work... I'm so used to the L-wrenches).

There shouldn't be any problems. I've shot my ar15 with conversion lots without and modification to my gb. Still shoots fine. Question is, how much will you be shooting to get leading in the gb and tubes...if a few thousand per year, I don't see why it'll be an issue...few hundred thousand... maybe an issue.

I doubt it would be thousands. I'm probably just being anal/paranoid about it.

[protohyp]

[caliguy93]

This should help.

Very low priced adjustable gas blocks in all barrel diameters. Iv bought many and they are all good to go!

https://www.bte-usa.com/bte-set-screw-micro-gas-blocks

[FeuerFrei]

22 conversions are great for your AR type clones.

I follow this 2 step procedure:
Scrub the chamber and wipe it dry BEFORE you insert the 22 conversion unit.
Remember to finish your 22lr session with 223 before you pack up. Blows the crap out of the gas system as noted in the above posts. 1 rd seems to work for me.
This has kept my AR's reliable after switching back and forth.
*I shoot a LOT of wolf 223 in my AR clones so I'm used to the dirty nasty etc..

[Grumpyoldretiredcop]

I wouldn't routinely move the gas block. The screws are knurled at the bottom, but repeated tightening and loosening will flatten the knurling and reduce their grip. Do it enough and you may be finding the gas block creeping forward when you're firing centerfire rounds, turning your rifle into a single shot. Better to get an adjustable block if you're that worried about debris getting into your receiver.

BTW, I shot a lot of rounds with a conversion kit before building a dedicated rimfire carbine and other than some extra work cleaning, there were no issues.

[xxINKxx]

Waste of time. Just shoot it as is with the 22lr kit. A couple rounds of 223 will blow anything out. You can blast the gas tube out with aerosol carb cleaner and use the straw tip and directly blast into the tube if you must.

Ive shot at least 10 thousand rounds straight with a drop in ciener kit and switched to 556 and it was perfectly fine. All the carbon from 22lr mainly builds up in the chamber and fire control group since its a blow back.

[Dale's Dead Bug]

Thanks all. I'll just run it regular with a couple 5.56 cleanup rounds.