technical suppressor question ??

[Mobuck]

Our trust owns a Spectre II rimfire and this weekend I was comparing it's performance to a very simple and basic Form 1 tube that an acquaintance brought over. Test hosts were a Ruger 4" 22/45, 10-22 w/16.5", and 17 HMR w/16.5".
The Spectre was hands down winner on the 22/45. HV or subsonic no real diff.
About a tie with the 10-22 using subsonic and we couldn't reach an agreement on the HV ammo.
The HMR was revealing as the Form 1 tube was noticeably quieter than the more "efficient" Spectre.
External tube size was close but no idea about the internal volume. So why was the Form 1 tube less effective on the 4" pistol but more effective on the HMR?

 

[Sharkbite]

Hmmm...

I just form 4'd a Spectre, specifically to use on a 17hmr rifle. My current 22 can is a Warlock and wouldnt handle 17hmr pressures.

I hope I'm happy with the sound reduction of the Spectre

 

[Mobuck]

I would rate the HMR reduction down to the level of a 22 short. It's difficult to get a subjective estimate w/o side by side comparison and we didn't have the time or inclination to dig up other ammo to compare. I can say the 16.5" HMR is an obnoxious little critter so the reduction is fairly significant. I have 60% hearing loss but I feel comfortable shooting the 16.5" HMR with the Spectre w/o ear protection.
I just don't quite understand the different results from the varied hosts. In trying to make impartial comparisons, we had the "listener" move slightly away from the shooter and not peek. As it played out, I felt his Form 1 tube was quieter than my Spectre on the 10-22 while he was opposite so it wasn't a "mine vs yours" thing.

 

[Deja vu]

I have 2 22lr suppressors (3 if you count the mystic X) all 3 do better on different fir arms. On my bolt action 22 the sparrow sounds better on the Walther P22 the Element2 sounds better. The Mystic X is not as good at the other ones but its a 9mm silencer that can play 22lr.

I also have a 17 HMR marlin bolt gun. On that gun the Element 2 sounds better than the sparrow.

Its all different. Wish I could be more help.

If you are dead set on what is the quietest you need to find a place that will let you try out suppressors before you buy and bring in the gun you want it on. That is what I did with a 9mm can. I wanted it to work on 357 magnum which eliminated alot of them. After that I went to a shop that had several suppressors and my friend also brought in his 2 9mm suppressors. In the end the Mystic (I got the Mystic X) was the quietest on my Ruger 77/357 to my ears. That bolt gun with factory 158 grain 38 specials (not +p) is laughable quiet.

p.s. the fact that I can use it on full power 223 and 300 Black out (with a 16+ inch barrel) also impressed me. It also works on a 30-30 which also appeals to me.

 

[Theohazard]

Different baffle designs work differently depending on what you're shooting through it. For example, the baffles on most 5.56 silencers are designed quite a bit differently than the baffles on most .22 silencers even though the bullet is very similar in size; the 5.56 silencer doesn't just have a larger size with stronger construction. Here's a cutaway of an AAC M4-2000:

Here are the baffles on a Spectre II:

And here are the baffles on an Element 2, which is a more typical .22 baffle design:

So it appears from your testing that the Spectre 2 was more efficient when firing lower-velocity, lower-pressure rounds like .22, and the Form 1 silencer had a baffle design that worked better with the higher-powered .17 HMR.