[Scratchammo]

I had an idea of adding a muzzle suppressor to an already integrally suppressed short barrel thus eliminating the need for subsonic ammo. Would this idea work in making it even quieter? I'm aware that this would be an SBR.

[c3shooter]

Subsonic had to do with noise made by the bullet IN FLIGHT. Not at the muzzle. A supersonic bullet breaks the sound barrier. Make high pitched KER-RAAACK sound. Suppressor has nothing to do with that.

[Scratchammo]

That's why my idea is to use a short barrel, to eliminate the need for subsonic ammo.

[BillM]

You want to get the barrel short enough that the bullet exits suppressor
at a speed below the speed of sound?

What caliber? The idea has merit. It works with 22LR--ammo that is supersonic out of a rifle can be subsonic out of a pistol--but if you are
starting with something like 223 the barrel is going to be REALLY short.

[Scratchammo]

Originally Posted by BillM

You want to get the barrel short enough that the bullet exits suppressor
at a speed below the speed of sound?

What caliber? The idea has merit. It works with 22LR--ammo that is supersonic out of a rifle can be subsonic out of a pistol--but if you are
starting with something like 223 the barrel is going to be REALLY short.

It'd be a 10/22 Pocket Rifle in .22lr. The barrel would appear to be full length however due to the extra suppressor. I think it'd be cool to use bulk Wally World ammo without hearing the loud crack associated with it. Theoretically it should be mouse-fart quiet.

[BillM]

I shoot a lot of bulkpak Federal AutoMatch. I get it at Wallyworld.

From my Ruger 22/45 with a 4" or so barrel, with a Liberty Kodiak
TL can, it's sub-sonic.

From my Savage MKII FV-SR with a 16" barrel, same can, it's got a
nasty little supersonic "crack" to it.

So somewhere between 4" and 16" it drops subsonic. Haven't tried
it yet with a new Tac-Sol SBX barrel, which is around 12".

[Scratchammo]

Originally Posted by BillM

I shoot a lot of bulkpak Federal AutoMatch. I get it at Wallyworld.

From my Ruger 22/45 with a 4" or so barrel, with a Liberty Kodiak
TL can, it's sub-sonic.

From my Savage MKII FV-SR with a 16" barrel, same can, it's got a
nasty little supersonic "crack" to it.

So somewhere between 4" and 16" it drops subsonic. Haven't tried
it yet with a new Tac-Sol SBX barrel, which is around 12".

12" sounds about right. I guess I'll have to check the velocities per barrel length for the popular brands.

[JonM]

if im not mistaken integral suppressed 10/22 with a full barrel bleeds off enough gasses to make standard velocity subsonic at the muzzle.

if you add a extra suppressor your not bleeding off the gasses before the bullet generates enough energy so even using 7 or 8 supressors if it was possible wont do a thing to suppress the supersonic crack once the round passes the speed of sound.

[Scratchammo]

Originally Posted by JonM

if im not mistaken integral suppressed 10/22 with a full barrel bleeds off enough gasses to make standard velocity subsonic at the muzzle.

if you add a extra suppressor your not bleeding off the gasses before the bullet generates enough energy so even using 7 or 8 supressors if it was possible wont do a thing to suppress the supersonic crack once the round passes the speed of sound.

I see what you're saying, the external suppressor is inherently a barrel itself. Do you know where I could find velocities in various suppressors?