Form 1 build material sourcing?

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d_lish
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Form 1 build material sourcing?

Post by d_lish »

Hey everyone!

So I just received my first tax stamp and will be doing a form 1 build. I'm not a machinist by any means so I wanted to source everything I could and do as little fitment as possible. I see a bunch of things online that makes me pretty confident I can piece something together without too much cursing. Even something that could quiet down my 7.5" 300 aac perhaps a 30-30 lever action (if I can find a reasonable price to thread the barrel).

Anyone have good things or bad things to say about any machine companies they might have ordered online from? Or even maybe what kind of quality I can really expect from them?
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Re: Form 1 build material sourcing?

Post by Zero99z »

First, I got a question for you: how long did it take to get your stamp? I submitted mine a few weeks ago.

Look up solvent traps. I'm not a machinist either (unless you count poor man's machining), but I am a welder, so I'm sourcing a combination of almost finished parts and unfinished stock.
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Re: Form 1 build material sourcing?

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Took a little over a month, even with me screwing up the paperwork twice, it was my first time, so I was shooting in the dark.

I did end up ordering machined parts from diversified machine and solvent traps direct. Solvent traps direct has very quick shipping and I received cups in under a week, which are very nice quality if I say so.
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Re: Form 1 build material sourcing?

Post by Dunkman »

I am still waiting for parts from Diversified Machine from Jan 24th. Hopefully yours are a faster turnaround than mine..
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Re: Form 1 build material sourcing?

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Which cones did you get from STD?
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d_lish
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Re: Form 1 build material sourcing?

Post by d_lish »

I got the 60 degree cones, 1 Ti, and 13 aluminum for a 10" suppressor, the ones I received have 3/4" skirts which I do plan to cut down in some way (pipe cutter?). The cups have .018 thick skirts on the aluminum and .027 skirt on the Ti. I won't be able to measure the cone area until after the arrival of some tools though. :roll:
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Re: Form 1 build material sourcing?

Post by ECCO Machine »

d_lish wrote: Tue Mar 10, 2020 5:25 pm The cups have .018 thick skirts on the aluminum.
I don't even go that thin on rimfire baffle skirts, which are much smaller diameter, half the length, and I use alloy 7068-T6511, which I can pretty well guarantee your cups are not; 7075 if you're lucky, good chance they're 6061.

Best of luck. Be very gentle with it.
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Re: Form 1 build material sourcing?

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d_lish wrote: Mon Mar 09, 2020 4:58 am Took a little over a month, even with me screwing up the paperwork twice, it was my first time, so I was shooting in the dark.

I did end up ordering machined parts from diversified machine and solvent traps direct. Solvent traps direct has very quick shipping and I received cups in under a week, which are very nice quality if I say so.
So, I'll probably get mine any day now.

For my 50 cal can, I already made the mount using raw stock and parts I modified, along with the original brake on my rifle. I'm using 1.749 diameter formed freeze plugs for the baffle stack, and everything else is gonna be raw stock.
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Re: Form 1 build material sourcing?

Post by Dunkman »

Just received shipment notification from Diversified Machine. Will be 7 weeks tomorrow from order date, in case you are wondering on lead times.
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Re: Form 1 build material sourcing?

Post by d_lish »

ECCO Machine wrote: I don't even go that thin on rimfire baffle skirts, which are much smaller diameter, half the length, and I use alloy 7068-T6511, which I can pretty well guarantee your cups are not; 7075 if you're lucky, good chance they're 6061.

Best of luck. Be very gentle with it.
Yeah..I was afraid someone would say something to that effect. I was planning on running subs only, but after reading your input, I think I may opt for a bunch more Ti baffles and use the aluminum ones for the last few? not sure.

I ended up measuring all of the aluminum cups and did get about half with .022" sidewalls, so maybe I'll use those over the thinner ones.

Maybe I need to buy a .22 so I have a reason to build a .22 suppressor? :lol:
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Re: Form 1 build material sourcing?

Post by d_lish »

Dunkman wrote: Thu Mar 12, 2020 11:37 am Just received shipment notification from Diversified Machine. Will be 7 weeks tomorrow from order date, in case you are wondering on lead times.
Thanks for the update dude, hell, with wait times like that maybe I'll start another form 1 and order a SDtactical tube to keep me busy! :wink:
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Re: Form 1 build material sourcing?

Post by Dunkman »

Can't go wrong with another Form1! I'm not saying yours will take as long as mine, maybe they are getting caught up on orders. Depends on order size too I'd imagine.
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Re: Form 1 build material sourcing?

Post by d_lish »

Zero99z wrote: So, I'll probably get mine any day now.

For my 50 cal can, I already made the mount using raw stock and parts I modified, along with the original brake on my rifle. I'm using 1.749 diameter formed freeze plugs for the baffle stack, and everything else is gonna be raw stock.
You gotta post some pics of that bad boy once you get it started, I'm interested to see how you have it set up. Did you use a forming tool of any particular kind or MacGyver something?
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Re: Form 1 build material sourcing?

Post by ECCO Machine »

d_lish wrote: Thu Mar 12, 2020 12:08 pm Yeah..I was afraid someone would say something to that effect. I was planning on running subs only, but after reading your input, I think I may opt for a bunch more Ti baffles and use the aluminum ones for the last few? not sure.
The problem with such thin skirts on aluminum baffles (and not necessarily just aluminum ones) is that they can do one of two things, or a combination, under higher pressure and at higher temperatures. The tube does help support them, but unless they're nearly a press-fit, those thin skirts lend to crumpling and/or the front of the skirt trying to ride up over one side of the next one and wedge itself in between the tube and the next baffle. Remember, force=pressure * area, so if you have a 1.5" diameter part being acted upon by a couple thousand pounds per square inch pressure, those thin skirts are having to resist about 3,500 pounds of compressive force no matter how far forward they are in the tube.
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Re: Form 1 build material sourcing?

Post by d_lish »

ECCO Machine wrote: Thu Mar 12, 2020 10:02 pm
The problem with such thin skirts on aluminum baffles (and not necessarily just aluminum ones) is that they can do one of two things, or a combination, under higher pressure and at higher temperatures. The tube does help support them, but unless they're nearly a press-fit, those thin skirts lend to crumpling and/or the front of the skirt trying to ride up over one side of the next one and wedge itself in between the tube and the next baffle. Remember, force=pressure * area, so if you have a 1.5" diameter part being acted upon by a couple thousand pounds per square inch pressure, those thin skirts are having to resist about 3,500 pounds of compressive force no matter how far forward they are in the tube.
Crap, I didn't even think about that.. Looks like I'm scrapping the aluminum all together for this build anyways. I thought from what I was reading about subs being lower pressure that I could get away with using it outside the blast chamber, but I really don't wanna be that guy whose form 1 exploded shrapnel all over the range.

Now I'm wondering what to do here. Getting the same kind of cups in Ti is gonna be quite the price tag, 44.99 a cup. I'm almost wondering if a SOT can core it for cheaper and with more expertise. Or... for the price of the Ti I can get an Ebay lathe and learn to machine 8)

Ecco, thanks for the input!
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Re: Form 1 build material sourcing?

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d_lish wrote: Thu Mar 12, 2020 5:12 pm
Zero99z wrote: So, I'll probably get mine any day now.

For my 50 cal can, I already made the mount using raw stock and parts I modified, along with the original brake on my rifle. I'm using 1.749 diameter formed freeze plugs for the baffle stack, and everything else is gonna be raw stock.
You gotta post some pics of that bad boy once you get it started, I'm interested to see how you have it set up. Did you use a forming tool of any particular kind or MacGyver something?
I'm buying them preformed from wedge machine.
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Re: Form 1 build material sourcing?

Post by Zero99z »

ECCO Machine wrote: Thu Mar 12, 2020 10:02 pm
d_lish wrote: Thu Mar 12, 2020 12:08 pm Yeah..I was afraid someone would say something to that effect. I was planning on running subs only, but after reading your input, I think I may opt for a bunch more Ti baffles and use the aluminum ones for the last few? not sure.
The problem with such thin skirts on aluminum baffles (and not necessarily just aluminum ones) is that they can do one of two things, or a combination, under higher pressure and at higher temperatures. The tube does help support them, but unless they're nearly a press-fit, those thin skirts lend to crumpling and/or the front of the skirt trying to ride up over one side of the next one and wedge itself in between the tube and the next baffle. Remember, force=pressure * area, so if you have a 1.5" diameter part being acted upon by a couple thousand pounds per square inch pressure, those thin skirts are having to resist about 3,500 pounds of compressive force no matter how far forward they are in the tube.
I'm not using any aluminum. These are the ones I'm using. They're just under 1/16"
https://www.wedgemachineworks.com/produ ... -stainless

They seem to have some good stuff.
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Re: Form 1 build material sourcing?

Post by d_lish »

Yeah, using those stainless for baffles are probably a way better bet. I may have to place an order with them this weekend so I can get this build going. Thanks for the link.

Got a shipment notification from DM, so I'm excited about that.
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Re: Form 1 build material sourcing?

Post by Zero99z »

I'm just waiting on my stamp to order them. Hopefully I'll get it next week.
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Re: Form 1 build material sourcing?

Post by d_lish »

So how much clearance would be ideal for a suppressor you want to remain serviceable? Shooting mostly subs will result in some pretty substantial carbon buildup I'd imagine, making it harder to remove the stack. Would .010" be too much play between the ID of the tube and the OD of the cups ya think?
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Re: Form 1 build material sourcing?

Post by ECCO Machine »

d_lish wrote: Sun Mar 15, 2020 9:04 am So how much clearance would be ideal for a suppressor you want to remain serviceable? Shooting mostly subs will result in some pretty substantial carbon buildup I'd imagine, making it harder to remove the stack. Would .010" be too much play between the ID of the tube and the OD of the cups ya think?
.010" is pretty loose, and looser fits leave more places for carbon to accumulate, among other issues.

.003"-.006" diametral clearance is what you want to shoot for.
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Re: Form 1 build material sourcing?

Post by d_lish »

ECCO Machine wrote: Sun Mar 15, 2020 11:00 am

.010" is pretty loose, and looser fits leave more places for carbon to accumulate, among other issues.

.003"-.006" diametral clearance is what you want to shoot for.
Awesome man thanks.

I ordered DM "select" tubing which ID is +/-.003" of 1.360" and WMW stainless solvent cups which have an OD of 1.357". Might have some tight spots, but those I can deal with.
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Re: Form 1 build material sourcing?

Post by d_lish »

#40Fan wrote: Mon Mar 09, 2020 6:30 pm Which cones did you get from STD?
ECCO Machine wrote: Wed Mar 11, 2020 9:39 am

I don't even go that thin on rimfire baffle skirts, which are much smaller diameter, half the length, and I use alloy 7068-T6511, which I can pretty well guarantee your cups are not; 7075 if you're lucky, good chance they're 6061.

Best of luck. Be very gentle with it.
Image

Image


STD, aluminum 60 degree, one of the one's with .022" skirt, no center mark, 11.99 each

Image

Image

STD, Ti 60 degree, .027" skirt (roughly) actually discovered about .005" of variation up to .032", center drilled on inside, 44.99 each
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Re: Form 1 build material sourcing?

Post by #40Fan »

I had a customer send me one a while back. I just checked the skirt and it is .038" thick. After looking at it, I see why they went thinner. The I.D. of the skirt on the one I have is smaller than the O.D. at the base of the coned section. No way this one would have stacked onto another one. There's plenty of meat to move that O.D., but I think they took the easy route and just make the skirt thinner.
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Re: Form 1 build material sourcing?

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#40Fan wrote: Mon Mar 16, 2020 6:03 pm I had a customer send me one a while back. I just checked the skirt and it is .038" thick. After looking at it, I see why they went thinner. The I.D. of the skirt on the one I have is smaller than the O.D. at the base of the coned section. No way this one would have stacked onto another one. There's plenty of meat to move that O.D., but I think they took the easy route and just make the skirt thinner.
Well now I'm disappointed, just got my caliper micrometer in the mail and the OD on the STD cup is fricken 1.347" at the widest point, quite a bit of slop from what ECCO said earlier. That's on the Ti cup too, they don't have an exact size listed for the diameter just D-cell, isn't there a agreed upon size for D-Cell components? Live and learn I guess..

But in other news, got the wedgemachineworks cups, their listed size seems to be pretty darn close, considering it's formed steel and not machined, within .003" of 1.357". Feeling pretty good about these.

Also, one of my DM orders arrived, Cherry bomb threaded muzzle adaptor, DAMN good fit on my Cherry bomb, Still waiting on tube and end cap. Orders were placed on Feb 28th, all were labelled in stock.
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