Form 1 300 AAC can. Almost finished

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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Wildcatter
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Form 1 300 AAC can. Almost finished

Post by Wildcatter »

I have almost finished my first form 1 can. All I have left to do is weld the end caps engrave, and thread for barrel mount.

The tube is 0.065", 1.625" diameter 316 SS with cones and spacers. I used 0.400 spacer wall thickness so the interior of the can is around 1.320. I made a thick short stepped blast baffle set 2.100 in front of the muzzle and spaced a smooth 60 degree cone 1.100" I front of that. The blast baffle has 6 radial 0.125" holes drilled to present gasses to the fist cone along the slope. I then placed three 55 degree cones with small steps spaced at 0.800", 0.600", and 0.500. I spaced the last baffle 0.400" off of the end cap and turned a smaller stepped cone on the interior of the end cap. Total length is 7.875". I left the cones a little heavy so I can use the can on a 308. It weighs in at 32 oz. a little heavy but acceptable to me for my first try and intended uses.

Tomorrow I weld and engrave. Test fire on a bunch of different rifles is planned for next weekend.

If I could figure out how to post pics, I would love to do so.

Thanks,

---Catter
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

Wildcatter wrote:I have almost finished my first form 1 can. All I have left to do is weld the end caps engrave, and thread for barrel mount.

The tube is 0.065", 1.625" diameter 316 SS with cones and spacers. I used 0.400 spacer wall thickness so the interior of the can is around 1.320. I made a thick short stepped blast baffle set 2.100 in front of the muzzle and spaced a smooth 60 degree cone 1.100" I front of that. The blast baffle has 6 radial 0.125" holes drilled to present gasses to the fist cone along the slope. I then placed three 55 degree cones with small steps spaced at 0.800", 0.600", and 0.500. I spaced the last baffle 0.400" off of the end cap and turned a smaller stepped cone on the interior of the end cap. Total length is 7.875". I left the cones a little heavy so I can use the can on a 308. It weighs in at 32 oz. a little heavy but acceptable to me for my first try and intended uses.

Tomorrow I weld and engrave. Test fire on a bunch of different rifles is planned for next weekend.

If I could figure out how to post pics, I would love to do so.

Thanks,

---Catter
Look forward to pictures, that can will probably handle 338lapua.

2 pounds is a heavy heavy heavy can!

Glad it works for your purposes!
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

The can interior is actually 1.400". I made every component out of 316 SS. Just abrasive blasted the tube. Not going to paint as it looks pretty slick as is.

I was a little nervous to go too thin with the baffles and caps as this is my first rodeo. One of liberty's monocore 223 cans weigh in at 27 ounces so I figured I could live with the weight. I'll use it for 223 full auto without worry.

---Catter
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

So do you think I could turn the front half of the tube to 0.500" and be okay for 223 and 308? I am not welding the baffles to the spacers.

Thanks for any insight.

---Catter
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

If you asked for advice on the forum you could have easily shaved of 5-8 ounces if not more.

Normal wall thickness on commercial cans is anywhere from .065-.075

Just a little tidbit about how much thicker your can is.
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

So without welding baffles to spacers, you can still reduce the outer tube from 0.065"? I have read quite a bit on this forum, back to 2007, and I thought the outer tube needed to stay at .0650 unless I welded the core.

I guess I should have asked a few questions about baffle thickness prior to pressing my internals into the tube but I'm pretty proud of this build, at this point. If it works, I'll be motivated to build another one.

I'm not that concerned about the weight at this point. If the build seems to handle poorly, it's just another $200 and another six month wait :-)

So how do you post pics on this forum?

Thanks for your input,

---Catter
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

Wildcatter wrote:So without welding baffles to spacers, you can still reduce the outer tube from 0.065"? I have read quite a bit on this forum, back to 2007, and I thought the outer tube needed to stay at .0650 unless I welded the core.

I guess I should have asked a few questions about baffle thickness prior to pressing my internals into the tube but I'm pretty proud of this build, at this point. If it works, I'll be motivated to build another one.

I'm not that concerned about the weight at this point. If the build seems to handle poorly, it's just another $200 and another six month wait :-)

So how do you post pics on this forum?

Thanks for your input,

---Catter
I misread it, your wall thickness is fine, get your baffles thinner as well as your endcap.

Upload your pictures onto the internet, then when you are typing a post take the link to that picture, and hit the IMG tab at the top of the text window. Insert your link in between the IMG's that show up in your text window.
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

Got it. Thanks. I'll try try to find a host for my pics tomorrow and upload.

So, from what I'm gathering, my can probably won't burst on the end of my barrel? :-)

I'm going to submit another form 1. Besides weight, I think I can make about 5 improvements to my design.

Thanks again,

---Catter
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

Image

I made two more lightly stepped 55 degree cones like the part second from left. I lightened the caps quite a bit after I took this pic. Obviously, not enough :-). The sketch is from earlier musings on suppressor designs. Didn't follow that path.

Image

Image

My 300 AAC barrel and suppressor combo measures 15.875". Had to make sure it was short if I was paying for 2 stamps.

---Catter
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

With just what i see you should be able to take off at least 6-8 ounces.

Your can should weigh no more than 20 ounces with that design.

Is your cone hollowed out on the underside? If not all you are doing is creating a tunnel for the gases to funnel out through.
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

Each 55 degree cone has a max wall thickness of 0.90. The first cone in front of the blast baffle has a wall thickness of 0.130, way too heavy. The blast baffle is a 0.160 thick disk. All cones are relieved at 60 degrees under the skirt, cut with a cobalt end mill on the lathe. I chose to create shoulders to index each spacer and the baffles all index the outer tube wall. The resulting shoulder between the spacers, I left 0.100 thick.

Much weight savings could be had. But...how do you think it will suppress?

Interior volume-wise, I am still just over most maker's 1.5" diameter, 8"-long 308 cans.

Thanks,

---Catter
Last edited by Wildcatter on Sun Nov 04, 2012 1:35 am, edited 1 time in total.
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delta9mda
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Re: Form 1 300 AAC can. Almost finished

Post by delta9mda »

Thin those baffles to .065"
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

I think you will be disappointed with the suppression the way it is, thin it out and it will increase internal volume.
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daviscustom
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Re: Form 1 300 AAC can. Almost finished

Post by daviscustom »

You could loose a ton of thickness off the front cap.......it could be thinned down to at least the .07-.05" ballpark depending on how much it will be abused.

You may want to retain some thickness around the outside edge where it goes into the can, but 3/4 of the thickness that goes past the front edge of the tube doesn't need to be there.

And you can drill a circle of holes around the threaded mount....either from the inside if you still have access, or the outside if you don't. (Obviously don't go all the way through the end cap.)
The myopic majority will be our republic's undoing.
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twodollarbill
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Re: Form 1 300 AAC can. Almost finished

Post by twodollarbill »

delta9mda wrote:Thin those baffles to .065"
+1.......you can thin your spacer walls down to .035" - .040"
Like others here have said...you'll appreciate the results if you lose some weight 8)
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

Well, I ran 240 grain Matchkings at 1000fps and 110 grain VMax at 2050fps. My can worked very well. The supers were noticably quieter that the 22" barreled Marlin 22 I shot along with it. The subs were just ridiculously quiet. I am very pleased with the rig. Did some night-fire videos as well. There was a little flash out of the end of the suppressor with supers and just some sparks with the subs. I couldn't be more proud.

Going deer and hog hunting with this rig next weekend.

Now I need to send off Form 1s for a general purpose 22 can and a 45 SMG can, and that will cover my needs.

---Catter
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Re: Form 1 300 AAC can. Almost finished

Post by MMH »

Is the supressor permanantly mounted to the barrel?
Wildcatter wrote:Image

I made two more lightly stepped 55 degree cones like the part second from left. I lightened the caps quite a bit after I took this pic. Obviously, not enough :-). The sketch is from earlier musings on suppressor designs. Didn't follow that path.

Image

Image

My 300 AAC barrel and suppressor combo measures 15.875". Had to make sure it was short if I was paying for 2 stamps.

---Catter
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

The can and SBR have their own tax stamps. It's removable. I have tried the can on a 10.5" 223 and a 3.5" 22lr. Very flexible suppressor. I'm going to send off a form1 for a 22 can next. Will go with K baffles in stainless for that.
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Bendersquint
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Re: Form 1 300 AAC can. Almost finished

Post by Bendersquint »

Did you take any of our suggestions and put it on a diet?
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Re: Form 1 300 AAC can. Almost finished

Post by L1A1Rocker »

Congrats on your build. Thank you for posting.
Wildcatter
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Re: Form 1 300 AAC can. Almost finished

Post by Wildcatter »

I left it as I finished it. Carried it for 25 miles over a week of deer hunting on the 8" blackout AR. Didn't notice the weight much. Took a nice buck, facing me, at 62 paces off-hand. Eotech sight. 125 gr Nosler ballistic tip chronographed at 1950 fps. Dropped right there with a neck/high chest shot. Bullet crushed 3 vertebrae, bounced down into the foreleg, breaking the humerus and lodged in the outside skin of the leg. Bullet weighed 82 grains, recovered. From filing for the stamps for rifle and can in late March, to planning the builds, making the barrel from a stainless blank, and the can from 316 stainless stock, then hunting my butt off, and ending up successful, this was in the top 2 hunting years of my life. Very rewarding.
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Re: Form 1 300 AAC can. Almost finished

Post by Homer »

G'Day Fella's,

Wildcatter, nice job well done!

JB
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