first design

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limeedgie
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Posts: 2
Joined: Fri Mar 20, 2020 4:36 am

first design

Post by limeedgie » Fri Mar 20, 2020 5:32 am

Hey all,
I've been thinking up of a design for my first form 1 can. I haven't bought anything but I'm going to be using an apogee 7.5" steel tube with an SDTA muzzle brake & mount. Apologies since I'm not a good sketcher, but here's what I've made so far. It's missing quite a few measurements but the parts are drawn to scale, if that helps. I'll try to give as many details as I can.
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The 3/4" skirt and skirtless cones are stainless steel. Everything's sized correctly, the only thing I'm unsure of is the muzzle brake since I'm basing my design off of one that is visually identical to SDTA just with different threading. My intended use for this can is to use on both my AR-15 and AR-10, but mostly the AR-15. My first question is about the baffle stack. I've read that more space between the baffles is better on rifle rounds than more baffles, so that points me to the 2nd design. But 6 baffles seems like I'm wasting the tube space. Am I going in the right direction with these designs?
The other question I have is about how much it would hurt the 5.56 suppression to have the can bore in .30 cal. Is it possible for a .375" bore to still decently suppress 5.56, or would it only work for 308? Any suggestions appreciated.
Last edited by limeedgie on Fri Mar 20, 2020 7:25 am, edited 1 time in total.

Gibs
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Joined: Tue Feb 11, 2020 4:21 pm

Re: first design

Post by Gibs » Fri Mar 20, 2020 6:30 am

For center fire rifles you'd be better off using skirted 60 degree cones. I'd go with 17-4 heat treated SS for the first 2 baffles to prevent erosion, .375 off the tip of your brake for the first one (use a spacer if necessary prior to the first baffle). Then either more of those or Ti for the rest. I'd say a minimum of 4 baffles, but 6 would be better. Blast chamber spacing should be around 2"-2.25". Spacing on baffles .675 first 2, then .5 for the rest and leave .375 spacer prior to the end cap. I'd do a .375 bore for all. Spend some time on the form1suppressor.boards.net READING and you can find over 100 pages of info to help you with your design. Good luck!

ECCO Machine
Silent But Deadly
Posts: 608
Joined: Tue Nov 28, 2017 7:34 pm

Re: first design

Post by ECCO Machine » Fri Mar 20, 2020 12:48 pm

Go with the skirted 60° cones, use 8 or 9 of them in your tube, depending on muzzle device protrusion into can. Start with the full .75" skirt, then .65, .6, .55, .5, .45, .4, .375, and make the final one pretty short where it butts to the end cap.

I run .30 bores at .370" with a single radiused clip 3/16" wide and .190-.225 deep, depending on cone thickness. In a ~8" can with 8 or 9 baffles, that will put muzzle end dBs lower than what's coming out the port of a 5.56 AR.
FFL07/02SOT Gunsmith & Machinist

Joel45acp
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Posts: 19
Joined: Wed Jul 31, 2019 11:09 pm
Location: San Antonio

Re: first design

Post by Joel45acp » Tue Mar 24, 2020 5:44 pm

ECCO Machine wrote:
Fri Mar 20, 2020 12:48 pm
Go with the skirted 60° cones, use 8 or 9 of them in your tube, depending on muzzle device protrusion into can. Start with the full .75" skirt, then .65, .6, .55, .5, .45, .4, .375, and make the final one pretty short where it butts to the end cap.

I run .30 bores at .370" with a single radiused clip 3/16" wide and .190-.225 deep, depending on cone thickness. In a ~8" can with 8 or 9 baffles, that will put muzzle end dBs lower than what's coming out the port of a 5.56 AR.
Can you post a pic of your single radiused clip.
Joel C


Jeremiah 29:11

limeedgie
New Member
Posts: 2
Joined: Fri Mar 20, 2020 4:36 am

Re: first design

Post by limeedgie » Wed Mar 25, 2020 3:46 pm

Thanks for your input guys. I've bought everything except the cones and will be able to get exact measurements of the caps and muzzle brake soon. Now I just have to find who makes 1.347" cones in 17-4.

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