9mm Form 1 Suppressor w/ AAC Style K-Baffles

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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Matt in TN
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Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

40 more hours of machine time on a 100% manual (we don't need no stinkin' DRO!) 1955 Southbend 9A lathe, and who knows how old Russnok mill, and my 9mm can is done. Machining operations are essentially the same as my 22LR can, but sized up for 9mm. That's all posted here in detail: viewtopic.php?t=138952 so I didn't bother taking pics along the way. Here's the finished product - deburred, cleaned, and ready for assembly:

Image

The booster assembly came from Ecco Machine (https://www.eccomachine.net/product-cat ... s-pistons/) and is a GREAT product! My blast baffle is 416 stainless, the other baffles are 7075-T6 aluminum, and my tube is 6061 aluminum. Final weight with booster assembly in the 6" configuration is 11.9 oz. In the 9" configuration it's 14.0 oz.

Here's the baffle stack and tube in the 9" configuration:

Image

And here's the 6" configuration after Gunkote, along with my 22LR suppressor:

Image
Last edited by Matt in TN on Sat Jan 13, 2024 3:48 pm, edited 2 times in total.
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
Matt in TN
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Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

Hmmm. Images are giving me this error: "It was not possible to determine the dimensions of the image. Please verify that the URL you entered is correct."

Image links so I don't lose them:

https://i.imgur.com/1NYSzSV.jpg

https://i.imgur.com/PFPtupc.jpg

https://i.imgur.com/RlIeD8c.jpg
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
Matt in TN
Silent Operator
Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

Here's the test video: https://youtu.be/CLjzrdariV8

Audio is terrible, as always. The head camera is a Sony HDR-AS50 that gives a better idea of the actual sound. The side view video is an iPhone and the audio from that is about useless - but it shows a better video angle.
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
Matt in TN
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Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

I did some temperature testing back in August that I forgot to report on. The big downside to using aluminum (even fancy 7075) is that it loses about half its strength when it gets over 300°F or so. So this thing is obviously not full auto rated - but I wanted to know if I had to worry at all about this during normal pistol shooting.

After a 5rd slowfire group shooting: no change in temperature at all.
After a 10rd mag dump (fast as I could pull the trigger): 115°F
After a 21rd mag dump: 140°F

All tests started with the can completely cool. So I'm thinking I have nothing to worry about! Part of me wants to do mag dumps until I hit 300°F just to know for sure - but the other part of me doesn't want to waste that much ammo. And when dafugk will I ever shoot multiple magdumps out of a suppressed pistol??? I'm good.
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
Matt in TN
Silent Operator
Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

When I first built this I really struggled with extremely poor accuracy issues, until I learned about how to "tune" a piston/booster/can assembly to a pistol. That fixed me right up and I'm thrilled with my accuracy now! Full details of the process here: https://www.silencertalk.com/forum/view ... 9#p1543919
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
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Capt. Link.
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Location: USA.

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Capt. Link. »

Matt that is a very nice can and I congratulate you. A+
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
milsurpcollector1970
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Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by milsurpcollector1970 »

Absolutely beautiful job on the baffles and machining for the booster.

Why didnt you clean up the outside of the tube a little?

From your work on the baffles I think you have the ability.
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Vidarr
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Location: United States

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Vidarr »

Nice work! I love that baffle stack.
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Matt in TN
Silent Operator
Posts: 88
Joined: Tue Jun 09, 2015 9:11 am

Re: 9mm Form 1 Suppressor w/ AAC Style K-Baffles

Post by Matt in TN »

milsurpcollector1970 wrote: Wed May 08, 2024 8:51 pm Absolutely beautiful job on the baffles and machining for the booster.

Why didnt you clean up the outside of the tube a little?

From your work on the baffles I think you have the ability.
Thank you sir! I blasted the tube with 220gr aluminum oxide and Gunkoted it, which cleaned it up nicely. No need to spend any machine time on it.
22: http://www.silencertalk.com/forum/viewtopic.php?t=138952
30: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=156481
9: http://www.silencertalk.com/forum/viewtopic.php?f=10&t=696697
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