I've been in the ATF queue for a Sparrow suppressor intended for a rifle for a while.

In the meantime, I picked up a 22 Compact, and put 4500 rounds through it before it needed a trip to the factory (take down lever died, they fixed it quickly with no complaints).

I got news my stamp was in, so I went back to some bookmarked threads on wrenches and adapters, and ordered the EWK (Sparrow-specific) adapter and wrench for the end cap.

Order came through in the predicted time (before the pistol came back). Getting the cap off the barrel was a major challenge, even with the wrench. They put those on to stay.

Took it to the range this week. I am very pleased with the fit and balance of the pistol, adapter, and Sparrow. The loudest noise was the sound of the bullet hitting the backstop. I put 200 rounds of CCI standard velocity through it.

Observations:
- The wrench fit perfectly, and yes, it will see more use, as I'm using the .22 compact for some situations where no one needs to think "suppressor".
- The adapter fit perfectly, but I did have to do a quick cleanup of some manufacturing debris in the threads.
- The Sparrow and adapter mated perfectly.

And for every silver lining ...
- I fired a box without the suppressor to check for issues with the adapter. The thread protector, hand tightened as best I can, given my arthritis, kept coming loose. Not sure which to complain about, but I'll pick one. Could the protector have some sort of lock to the adapter? Would have saved me chasing it down as it parted company. Maybe for shooting I'll just take it off.
- The gun is markedly dirtier after running the suppressor. I think I expected that just in principle.

And to answer questions others have asked -
- I saw a reasonable and acceptable (IMO) build up in the adapter. It was not enough to cause any issue, and cleared with a pad and some Hoppe's, in line with my normal cleaning after a range session.

Net net?
- I'm happy with the combo.
- EWK order was handled well, and product works.
- Unless you have extra hex wrenches, just buy one from EWK for $1.50. I later realized I was going to have to bust a set in my toolbox to put one in the range bag, so an extra is called for.

I, too, have a Sparrow on a M&P 22c. After learning the 22 and 22c used different thread adapters, I ordered my adapter from Twin Tech Tactical. It's a good adapter, had the shoulder SiCo recommends and it came with a thread protector. It also works very well with my newly-released Spectre II.

__________________
M&P's and K Frames Pleeze!

I'm thinking about getting the Twin Tech adapter. I asked in another thread, but figure I'll ask here too.. What are your thoughts after using it?

Also:
- does it index off the front of the barrel, or the shoulder?
- are the threads clean, any burrs or anything?
- is the o-ring engagement a snug fit? It should be .440 +/- .002 diameter

The EWK indexes off the shoulder and I found the threads on my copy fairly clean. The o-ring engagement area measured .436 on mine.

I have only used the adapter for 100 rounds with my Sparrow and I'm happy with it so far. Really like the 1/4 inch bit to remove the adapter instead of those tiny thin wrenches.

Received my EWK adapter for my M&P 22C to use with the Sparrow.

100% satisfied with fit, finish and quality, great communication from EWK.

Smith & Wesson M&P 22 Compact Thread Adapter Blued - $22.00 : EWK Arms