Suppressors 300 blackout can issue

[thebeast862]

I have an awc thundertrap and want to use it on my 300 blackout that I just purchased. I assumed that my can and rifle would be threaded for .308 (5/8 x24) but instead both are threaded 9/16 x24. I only really want to use it for sub sonic rounds so I was thinking maybe my awc Jupiter eye (.40 cal) would work because you can change the thread pattern on them. I called and they said it might work but it might be to much pressure for the can. My question is would it work or should I try a threaded barrel adapter. I really don't want to have to get my barrel and suppressor rethreaded plus new thread protector and my pelican case is already cut for that length barrel.

 

[jasonfaz]

With subs it most definintely will work. But make absolutely sure you're only running subs if you end up going with the pistol can. Ive run both the TiRant45 and TiRant9 on my 8.2" 300 BLK. I used a 5/8-24 to .578 x 28 adapter and they both metered under 130 dbs with factory 185 gr Gemtech subs and 194 gr Lehigh ME handloads. That said, your Thundertrap would be ridiculous quiet. My MK13-SD meters nearly 8 DBs quieter than my pistol cans on hosts with similar barrel lengths and gas systems using the same ammo.

Here's a stick i put together for somebody wanting to use a .45 cal pistol can...

 

[07yzryder]

sorry you lost me, if the can and rifle are both threaded for 9/16x24 where is the issue?

 

[thebeast862]

sorry you lost me, if the can and rifle are both threaded for 9/16x24 where is the issue?

Because my Ar is threaded for .308 which is a 1/16 larger diameter

 

[thebeast862]

Where did you get the thread adapter from. The one I read about most was made from tros but have not been able to get in touch with anyone this week.

 

[culater]

look up brownells they might have something

 

[jasonfaz]

Mark at TROS makes the best ones. Nice stainless steel versions. The one used in the rifle above was a black oxide one from the silencer store. This is it:
300 Blackout Adapter 45ACP .578X28 [300 Blackout Adapter 45ACP .578X] - $49.99 : The Silencer Store, The Silencer Store

 

[SABuzzard]

I'm missing something.... Is your can 5/8x24 and your barrel 9/16x24. Is that correct?

 

[thebeast862]

I'm missing something.... Is your can 5/8x24 and your barrel 9/16x24. Is that correct?

My savage .308 and can are both 9/16x24. My ar blk out is threaded for 5/8x24.

 

[ajwcotton]

If I am reading this correctly your AR barrel is 1/16 larger, but the same thread pitch. The best long term solution would be to have the barrel re threaded. Since it is the same pitch threads a decent smith shouldn't have any trouble turning down the major diameter and picking the threads back up. This would leave You with the same length barrel and the original crown you would only need a new thread protector.

 

[SABuzzard]

My savage .308 and can are both 9/16x24. My ar blk out is threaded for 5/8x24.

Ok - got it. That makes sense to me now.


Your best long-term solution is to re-thread the AR. As AJWcotton pointed out a smith should be able to size it down without having to cut/loose length. I've tried out a couple adapters on various cans and projects. They work, but never quite feel 100% to me. In every case I've ended up going back and re-threading to the can or brake's native pitch.