One thing I noticed on my 15-22 was it was louder than a same barrel length 10-22, I checked several things and found the S&W is louder due to ONE simple reason:
The barrel is threaded correct, HOWEVER it's threaded too deep.
I generally thread my 10-22 barrel down to .25, the S&W was .625 or .375 longer .
The S&W folks threaded the barrel to the same depth as a regular AR 15, which means you're losing a lot of the expansion chamber and pretty much screwing the suppressor all the way to the first baffle.
Easiest way to remedy it is by stacking normal AR15 crush washers back to back, in an hourglass config.
To some of you it'll mean nothing, but to me it really made a difference.

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Most .22 suppressor manufacturers recommend threading to .400" which is pretty much standard on pistols and pistol adapters. Most factory rifle threads are to .6xx" (standard ar) which is a little too deep as you found out. A couple places even make thread spacers for the purpose of setting the correct length. I have one for my 15-22, bit I can't recall where I got it right at the moment.

I never really thought about it till I tried putting a "regular" thread protector on and it came up way short.

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Don't stack crush washers. That's a baffle strike or endcap strike waiting to happen. Use a spacer. That's the best option after having it threaded to the correct specs.



Rifle Thread Spacer (1/2×28) | Silencer Shop

AR 15 Black Spacers (Three Pack) AR15 Spacer [] - $19.99 : The Silencer Store, The Silencer Store

+1 for the spacer.

i use the peel washer (cone shaped one that came with the birdcage) between the can and the end due to the same issue. perfect fit since it was an original part. markings on the cans don't index with the side, kind of on the bottom but i really don't care. spacers are avail at any true value type store since it is a common threading if you don't want to use the original washer. i actually found a thread protector there for the 15-22 that was the perfect size until i made it a permanent host for that can.

Washer and a precision machined spacer are two different parts. I would err on the side of caution and spend a few bucks for a spacer designed just for this problem. All my longer host that are factory threaded are too long. As someone else mentioned, handguns are good to go.

Do it right or....

The silencer store has 4 pkgs left in stock.

Baffle strikes are caused by a bad threading job and not what you space the suppressor with.
If your threading is correct, you could space it with Gummi worms, if your threading is off, nothing will help that.
However, to be sure, yes a spacer is the correct way to go.
Me, I'm just working with what I had around.

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