300 Blackout blast chamber length

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3strucking
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300 Blackout blast chamber length

Post by 3strucking »

I am going to file a form 1 for a 300 BO. Its going on a bolt gun shooting subs only. Is 1.500" too much blast chamber length for a bolt gun?
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fishman
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Re: 300 Blackout blast chamber length

Post by fishman »

Yes. Unless you're going for extra low backpressure
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
3strucking
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Re: 300 Blackout blast chamber length

Post by 3strucking »

I was looking at the SIG 762 as a example of what I want to build. It looks as if its close to that.
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fishman
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Re: 300 Blackout blast chamber length

Post by fishman »

And that can is rated for supersonic 308
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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T-Rex
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Re: 300 Blackout blast chamber length

Post by T-Rex »

It depends on which 762 suppressor you're referring. Sig has several models, not all the same.
The QD and DT (Taper-lok) have different chamber designs

Image

First, the Steel and Ti versions are vastly different lengths and one must know which this picture is of, before scaling. (my guess is Ti)
Second, you can't simply measure the blast length and scale, because of the conical and cylindrical differences.
Lastly, the Sig uses equalization ports, down the entire length of the baffle stack, and this must be accounted for in your design.

Image

fishman wrote:And that can is rated for supersonic 308
300Blk is the first caliber listed, for all of Sig's 762 suppressors.
The Ti versions (much larger volume) are said to work extremely well on 300Blk
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3strucking
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Re: 300 Blackout blast chamber length

Post by 3strucking »

Thanks for the info. I was curious about the porting on the baffles and your pics are a great help.
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fishman
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Re: 300 Blackout blast chamber length

Post by fishman »

T-Rex wrote:
fishman wrote:And that can is rated for supersonic 308
300Blk is the first caliber listed, for all of Sig's 762 suppressors.
The Ti versions (much larger volume) are said to work extremely well on 300Blk
Yes, but the point I was making is that the blast chamber of sig cans was designed to handle supersonic 308. That means that it likely isn't IDEAL for subsonic 300blk. even though it does a great job suppressing it, it might be slightly quieter or have less frp with a smaller bc.
300 blackout form 1: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=137293

5.56 form 1:
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=141800&p=955647#p955647
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