I just got a M&P22 and installed the adapater so I can run my Sparrow on it. I have installed it as tight as I fill comfortable by hand. As I shoot the adapater keeps loosening up. I plan on leaving the adapater on the gun for good. I see Loctite makes a high temp threadlocker but it is rated for 1/2" bolts way more than what I'm working with. So my ? is what could I use to stop the adapater from backing off so much or is this something I just need to get in habit of tighten every mag or so.
Gunsmithing loctite on thread adapater
- Thread starter KHOOKS
- Start date
I use a bit of hi-temp anti-seize compound on the threads and torque mine to about 30 foot pounds. This is on AR15 barrels, which SHOULD be the same threads/shoulder as the MP22. I have no trouble with the adapter backing off with my YHM QD Phantom.
You MUST have a good, square-cut shoulder behind the threads for the adapter to butt up against. If you don't have at least 1/2 x 28 threads to put the adapter on, don't do the above.
Also, the loctite you asked about should work fine as well, and I would think the blue 242 would be good enough on a .22. I'd try that first before I went to a more permanent type like the red 271. The 242 can be removed with normal tools-the 271 not so much.
Whichever way you go, you shouldn't have to put up with constantly re-tightening the adapter.
ETA: I'm a one-tooth, knuckle-dragging, redneck, shadetree mechanic and work on my guns the same way I would work on any other mechanical device. So far I have done so successfully, but don't take this as the last word on the subject. There are people here with far more GUNSMITH experience who may disagree with my methods. Like going to the Dr, get a second opinion before you jump out there and blindly follow anything I tell you. It works for me but YMMV.
You MUST have a good, square-cut shoulder behind the threads for the adapter to butt up against. If you don't have at least 1/2 x 28 threads to put the adapter on, don't do the above.
Also, the loctite you asked about should work fine as well, and I would think the blue 242 would be good enough on a .22. I'd try that first before I went to a more permanent type like the red 271. The 242 can be removed with normal tools-the 271 not so much.
Whichever way you go, you shouldn't have to put up with constantly re-tightening the adapter.
ETA: I'm a one-tooth, knuckle-dragging, redneck, shadetree mechanic and work on my guns the same way I would work on any other mechanical device. So far I have done so successfully, but don't take this as the last word on the subject. There are people here with far more GUNSMITH experience who may disagree with my methods. Like going to the Dr, get a second opinion before you jump out there and blindly follow anything I tell you. It works for me but YMMV.
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No it is not the 1/2X28 thread of the can to adapater that backing off it is the adapater to the 22 barrel which are more like a 1/4X28 or something small. I'll just keep my eye on it for now until I hear more about this issue. Maybe a small tig tick weld just to hold it in place.
If it's 1/4" (.250") thread on a .22 LR barrel (app .220"? bore), the wall thickness of the threaded portion would be like negative numbers at the root of the thread. Surely your suppressor is threaded something bigger than 1/2 x 28 if you need an adapter? I'm not poking fun here, just trying to help you out. I did understand it was the barrel-to-adapter fit that was giving you trouble.
If you intend to leave the adapter on the barrel for eternity then the red loctite you mentioned in the OP will definitely do what you want, just know that if you ever decide you want it off it will take some extreme heat and you may be better off just cutting the threads off and starting over.
I'd put some blue 242 loctite on it to at least put a stop to the aggravation of constantly having to re-tighten. The blue loctite can be removed with tools, and if it doesn't hold what you want it to hold you will get a second chance to take more extreme measures later. Welding and red loctite are much less forgiving if you need to do something else with it later.
Yea I hear you the 22 barrel is small and the end is threaded it then passes thru a sleave. ON the barrel the thread work to hold the barrel and chamber in place. It has a small barrel end cap that hold the works onto the sleave that mounted to the lower. The barrel end cap is removed to install the adapter so it is a very small set of thread about half the size of the 1/2X28. See this adapter:
P-22 Adapter with Thread Protector | Superior Silence
The thread you see is for the can to attach the thread I'm having issues with are the inside cut on the other end of the adapter. Not sure what size but small threads. Hope this helps with giving you an idea of the connection of the adapter to barrel. If not look at one of the M&P22 disassembly videos, also the same set-up on the Walther p-22.
P-22 Adapter with Thread Protector | Superior Silence
The thread you see is for the can to attach the thread I'm having issues with are the inside cut on the other end of the adapter. Not sure what size but small threads. Hope this helps with giving you an idea of the connection of the adapter to barrel. If not look at one of the M&P22 disassembly videos, also the same set-up on the Walther p-22.
OK--I understand it a little better now. I've never looked at a MP22 barrel to see how it was done. I'm at work and can't open any videos or anything.
Any other ideas on this?
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