We had a silencer shoot last year a bunch of people from this site as well as people from silencertests.com. Between all of us we probably had 20 cans or so and we played around with putting different caliber cans on different caliber guns.

It does not make a huge difference but you can definitely hear the difference. A silencer has baffles these are what trap the gas and suppresses the weapon. The tighter the tolerances the better it is going to do its job. If you use a .45 can on a 9mm for instance it leaves a large amount of room for the gasses to get around the bullet instead of getting caught in the baffles.

It will work and you can still shoot it without hearing protection but it will not be as effective as a 9mm can. Maybe we will have another silencer shoot this year and you can attend and listen for your self and then make the call on what you want to do. We also usually have quite a few suppressed weapons at our monthly shoots.

If you go to the club shoot forum and look about half way down there is the thread to our silencer shoot. Go to page 3 and there are pics as well as a video made by Alucard that you can watch. At the end of the video the guy shoots a .223 can then switches to a .308 can. You can hear Alucard say it makes a difference not a lot but a little.