"BiCore" option with Paul's 7.5K .223 MonoCore design

Yes, it can be legal to make a silencer. For everything Form-1, from silencer designs that are easily made, to filing forms with the BATF, to 3D modeling. Remember, you must have an approved BATF Form-1 to make a silencer. All NFA laws apply.

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calinb
Silent Operator
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Joined: Tue Feb 10, 2009 1:34 am

"BiCore" option with Paul's 7.5K .223 MonoCore design

Post by calinb » Tue Jan 03, 2012 3:47 am

I was looking over Paul's plans and thinking about building the can with a 3AL-2.5V titanium tube and light weight 7075-T6511 core.
viewtopic.php?p=743597#p743597

It struck me that the expansion chamber / ported tube section of the monocore could be machined in stainless steel to improve its blast erosion resistance, while machining the rest of the core in 7075. The change would not increase the overall length of the can significantly, if at all. The need for the take-down cap and threading insert would also be eliminated with this optional modification.

The threaded barrel attachment and ported tube sections of the monocore would be machined from a single piece of stainless bar and an appropriate threaded section added to the end of the ported tube (external threads on the tube). Then the threaded section at the end of the core could be eliminated along with the cap, and the o-ring groove and tube relief lip moved from the cap to the end of the core. The take-down threads would be moved from the end of the can to before the first baffle and the core's bore internally threaded to match the end of the ported and now threaded stainless tube. Take-down would be accomplished by unscrewing the 7075 core from the stainless ported tube.

Phew--that was a lot to say but it was easier than making a drawing and I hope it gets the idea across!

I have a kiln for heat treating and some 17-4 bar, so I'll probably use that.

What do you think?

The trust is done and now I just have to decide on three designs for three upcoming projects to know what lengths to put on the Form 1s. Based on the reports in this forum, it looks like I'll have to endure about half a year of infringement on my Second Amendment right before I get my stamps! :shock:

-Cal

Samson104
Silent But Deadly
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Re: "BiCore" option with Paul's 7.5K .223 MonoCore design

Post by Samson104 » Tue Jan 03, 2012 6:22 am

What caliber Are you running this on?

Look into 7068 aluminum it's head and shoulders stronger and harder than even 7075

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PaulNoiseLess
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Re: "BiCore" option with Paul's 7.5K .223 MonoCore design

Post by PaulNoiseLess » Tue Jan 03, 2012 7:04 am

Hi,

When I have to split the Blast and the Core (for larger Calibers than .223 or for Cores longer than 8 inches) i go either with a Dove Tail junction or a Bolt & Nut inside the Core. For both, I use a trusted geometry for aligment.

I don’t like screw/unscrew SS and Alu.

Best,

Paul
The future is not waiting for us, it is waiting within us ...

calinb
Silent Operator
Posts: 59
Joined: Tue Feb 10, 2009 1:34 am

Re: "BiCore" option with Paul's 7.5K .223 MonoCore design

Post by calinb » Tue Jan 03, 2012 2:45 pm

Samson104 wrote:What caliber Are you running this on?

Look into 7068 aluminum it's head and shoulders stronger and harder than even 7075
I'll look it up. Heat resistance seems to be the biggest deficiency with 7075, relative to alloy or SS.
PaulNoiseLess wrote:Hi,

<snip> I use a trusted geometry for aligment.

I don’t like screw/unscrew SS and Alu.

Best,

Paul
"Trusted geometry" (and adequate geometry tolerances that are ensured by design and fabrication methods) were my greatest concerns with my idea, Paul. I wasn't too worried about takedown, as long as a good anti-seize is used.

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