Quoted:
I'm new to suppressed pistols and have a question. Can a .40 caliber suppressor be used on a 9mm and even a .22 caliber pistol? Is the sound suppression degraded significantly by shooting an undersized round out of a larger caliber suppressor? Thanks for bringing me up to speed on this.
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yes...it will be slightly less efficient than a dedicated can for the intended caliber, but most everybody here does just what you mention...at least until they buy more suppressors. :D
it'd be fine on the 9mm, but most will say not to use it for 22LR, especially if the can is not servicable
the best recommendation, unless you're ready to jump in an buy a bunch of cans, is to buy a .45 pistol suppressor...so you can shoot .45, .40 and 9mm. That's what I did for my first pistol can and I don't even own a .45 at this time. Added a 22 can to the mix as well.
Same theory as buying a .30 cal rifle can to use for .308, 300BLK, 6.8mm and 5.56/.223.