What's happening here? Keyholing?

[Piglatinhater]

Look at the rear end of the threads. Some of them have no recess (Particularly ebay thread adapters). Thats where the rear end has a non threaded part that is just as large as the outside diameter of the threads. Meaning that the can cannot go past the threads and shoulder up against the front of the barrel. That is what keeps the can perfectly straight down the bore. If it doesn't it might still be real straight but not perfect. This will not cause a strike but make it tight enough to cause turbulence on one side and the bullet could tumble.
I see it pretty regularly. Almost 100% of the time this is what it is.

It's a factory SR22 thread adapter that came on the pistol.

 

[Wallace's]

It's a factory SR22 thread adapter that came on the pistol.

Picture? Even the big manufacturers mess up time to time. We could tell 100% if it's under cut or not.

 

[Nonliberal]

It's a factory SR22 thread adapter that came on the pistol.

Take a picture of the side of the threads for me. Whatever it is, we can get it straightened out.

 

[Piglatinhater]

Take a picture of the side of the threads for me. Whatever it is, we can get it straightened out.

See below

 

[Nonliberal]

See below
View attachment 1155580

That doesn't look like relief is the problem. May be on the inner threads of the adapter. You said it shoots straight on everything but this pistol?