Larger dia tube over baffle stack?

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yondering
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Larger dia tube over baffle stack?

Post by yondering » Tue Jul 26, 2016 11:47 pm

Have any of you tried a larger diameter tube over a normal sealed/welded baffle stack? I'm considering doing this, with a few small vent holes at the blast baffle, to use the space between the stack and outer tube as a secondary chamber. My hope is to pressurize that chamber, then bleed it back into the stack (through the same small holes) slowly.

This will be a 30 cal rifle can for 308, 6.5 Creed, etc, using clipped cones in a 1.375 OD stack; thinking about 1.625 or 1.750" Ti for the outer tube.

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RPM509
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Re: Larger dia tube over baffle stack?

Post by RPM509 » Wed Jul 27, 2016 8:02 am

Like a reverse reflex design where the extra volume is over the baffles instead of the barrel.
Interesting idea.
"a butt tuba" - Palindrome

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fishman
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Re: Larger dia tube over baffle stack?

Post by fishman » Wed Jul 27, 2016 8:24 am

I believe that's what's referred to as a coaxial design. It's been done, and from what I've read it works well on high pressure cartridges
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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mr fixit
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Re: Larger dia tube over baffle stack?

Post by mr fixit » Wed Jul 27, 2016 10:29 am

Similar to this?

ken226 wrote:I've done some testing over the last few weeks and i thought i'd post the results here.

I tested 4 suppressors, all on a LWRC 16 inch piston gun, caliber .223. The suppressors were all of my own manufacture, identical designs except as follows.

All were 1.625 od, 7 inches oal, .058 wall thickness.
#1 .275 bore, 7 baffles
#2 .275 bore, 5 baffles
#3 .365 bore, 7 baffles (designed for 300 blackout)
#4 .365 bore, 5 baffles (designed for 300 blackout)

The suppressors with 5 baffles had the same bafflestack length, the 1st baffle being the same distance from the rear endcap to accommodate the Yankee Hill flash hider. They just had more space inside between baffles.

No decibel meter, all by ear. The .275 bore cans were designed for .223 and the .365 bore cans were designed for 300 blackout. All were mounted via a Yankee Hill QD flash suppressor.

The best suppression was from #2. It was easily the quietest. Both the .275 bore suppressors were significantly quieter than the 2 .365 bore suppressors, but #2 also audibly quieter than #1 as well.

Bore diameter made a much bigger difference than i suspected, even moreso than the number of baffles.

After about 300 rounds, i put #3 on my bandsaw and cut it in half to make a cool paperweight.
Image

Found at this thread: viewtopic.php?t=129752#p904996

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yondering
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Re: Larger dia tube over baffle stack?

Post by yondering » Wed Jul 27, 2016 8:12 pm

mr fixit wrote:Similar to this?



Found at this thread: viewtopic.php?t=129752#p904996
Similar, except the blast chamber will be same OD as the baffles, and the outer chamber will only be connected by a few small holes. I have not settled on how small or how many.

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curtistactical
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Re: Larger dia tube over baffle stack?

Post by curtistactical » Fri Jul 29, 2016 1:09 pm

Yes if done correctly they work excellent.
Joseph Jones
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yondering
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Re: Larger dia tube over baffle stack?

Post by yondering » Fri Jul 29, 2016 9:07 pm

Good to know, thanks.

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