Suppressor coming loose after shooting

[Suppressorengineer]

I got a lot of questions about this so I made a video on youtube and Rumble to explain why a suppressor comes loose after shooting high volume. Discuss thermal expansion, temperature change, material properties of inconel 718 and 4140. Pertains mainly to square shoulder barrels and I will follow up with video about taper barrel shoulder how and why they are different. Please comment on the videos so I can enhance future videos and make videos people want. Not selling anything or promoting any firearm or suppressor brands on this channel. Here are the links to the videos
Youtube:

Rumble: https://rumble.com/v6u4oxx-suppressor-coming-loose-explained.html?e9s=src_v1_upp

 

[Albany Mountain]

What torque is usually applied during assembly ? Any Locktite or antsieze applied during assembly?

 

[Suppressorengineer]

What torque is usually applied during assembly ? Any Locktite or antsieze applied during assembly?

You can easily torque a direct thread suppressor to 30 ft/lbs. Hand tight is roughly 4-6 ft/lbs depending how strong you are. A lot of people only have them hand tight so they can easily move from gun to gun without needing a tool. Ceramic thread locking compound is what I would recommend for suppressor as they can take the heat. to remove ceramic thread lock you use hot water and not applied heat like other thread locking compounds. Anti-sieze is not needed in my experience.

 

[Tangent]

I just use some PTFE tape. It doesn't last forever due to the heat, but it's enough to stop it coming loose.

 

[shoot4fun]

I own several suppressors. All but two never loosen, as they are QD and not direct threaded.
One is made of aluminum and has a steel thread and my AR suppressor is Inconel. Both to them will loosen.

 

[Hunter2678]

From direct experience...on a semi-auto (i,e AR15) a QD mount locked in place with rocksett with a tapered shoulder (mine is YHM SRX) all but eliminates the can coming loose when hand tightened. If it's directly thread mounted and hand-tight, most times it will eventually loosen from the bolt cycling. Mil spec muzzle threads are notoriously loose, so they rarely seem to hold onto a direct thread can under prolonged firing.

On a bolt gun direct thread, hand tight should work fine as long as you have enough barrel face/shoulder to contact the back of your threaded can mount.

 

[HandgunHTR]

All of my suppressors are direct thread and none of them come loose now that I put them on correctly. Most people treat them like glass. You need to 1) ensure your threads are clean, both on the suppressor and the host barrel. That means no anti-seize or any of that crap. Properly threaded barrels will not gall unless you have junk in the threads or cross-thread it. 2) Spin the suppressor on until it is hand tight. Back it off 1/4 to 1/2 turn and then with a quick twist, snap it into place. Do it with force. Then crank on it some more. You will probably need a strap wrench to get it off if you let it cool before trying to remove it. An oven mitt comes in handy.

Using that method, I can shoot a couple hundred rounds at the range and not have it come loose at all. I can also carry it around for a week or more while hunting and also not have it come loose. This is equally true for all 9 of my direct thread cans.

 

[The boogalorian]

I have several suppressors at this point. I use the keymo quick mount. No issues with them loosening up even after multiple magazines. On my bolt guns I use a Thunderbeast Arms quick mount. The TBA needs to be tightened every 10-20 rounds.

 

[Coyotefurharvester]

Neither of my direct thread have ever loosen up. I use light coat of copper anti seize, hand tighten + 10 ft lbs with wrench. Both bolt and gas guns, whether shooting prairie dogs or riding in the truck hunting.

 

[1ofU]

i have 3 YHM cans with their QD , i stayed with them after my first
never had any come loose

 

[boltfluter]

Mine are direct thread. I use one drop of red locktite on a clean thread. Snap it on hand tight and go shoot it. It creates just a little drag when you remove the suppressor. But, mine do not shoot loose anymore.
Paul

 

[k260]

If it's a direct thread can and is constantly coming loose we tell our customers to use a Nord Lock lock washer, it's a two piece lock washer that is the only one I've seen that is dead parallel and doesn't cause alignment issues. We don't recommend using lock washers or crush washers because they generally cause alignment issues but the Nord Lock never has. You can snug it tight but it'll take two people to get it off, not recommended if you're constantly removing the can.

 

[5spd]

Both mine are direct thread, never had them loosen up during 100s of shots into pdogs. I tighten with both hands, tab of oil or greese on threads.

 

[FoxTales]

I suspect thread pitch may contribute . I have one rifle that is 1/2" unf , it's the only one that ever comes loose , never an issue with 18×1 .
Then again, over our side of the pond , few have a high round count compared to you guys .

Thread locking a moderator on seems counter intuitive since they should be removed before a rifle is put away . The condensate will destroy the crown and muzzle over time . Guess we do things slightly different over here .

If the rifling were right hand and the moderator thread left hand , would the loosening still be an issue ?

 

[Dave Zander]

Have a thunderbeast direct thread 5/8”-24 thread.
Straight 1.250” barrel , I snap it tight with hands, it doesn’t loosen. The 1.250” barrel gives a lot of face contact . It would loosen with heavy varmint barrels. I take it off all the time to case the gun. No issues.

 

[Clancy]

I can honestly say I’ve never had anything even act like it was coming loose- from thread protectors to brakes to suppressors. I grease the hell out of threads. Good equipment and good threads…. Who would have thought?

 

[USMCsilver]

My direct thread cans are rimfire and 9mm pistol. They don't usually loosen themselves because I use an o-ring.

I have several cans with ASR mounts, and they NEVER come loose. They are often actually are a bitch to remove after shooting and they have anti-seize on them.

Then, there's the tri-lug stuff. Obviously, zero problems there, too.