I recently bought a M&P 22 compact with the threaded barrel. I put my dead air mask 22 on and shot it with my wife. We both noticed blowback with particles hitting our face, which actually stung quite a bit. We shot various CCI ammo (mini mag, varmit, target, and subsonic) in 36 and 40 grain. It didn't happen with every shot and we couldn't really tell if it was ammo specific. I've read that this may happen when the the action opens early, and is sometimes prevented by a heavier spring. Some suppressor ready pistols come with two springs for this reason.

Does anyone have any advice for this problem, or experience with this? With the 22 compact specifically or another gun? It was pretty disappointing and would be great if I could fix this problem. Other than that the gun with the can was fun to shoot and pretty quiet.

Any suppressor will increase backpressure, but the amount of blowback you get is going to be dependent on several variables... gun, suppressor, ammo, etc.

I run a DA Mask on my M&P 22 compact and get little to no blowback, but I run CCI standard velocity almost exclusively. This combo is very near my favorite suppressed setup to shoot.