I'm drawing up a can for .223/5.56 use. Semi only no full-auto. 1.625"x12" with about 7.5" hanging past the muzzle.
It's going to use basic K-Baffles with a 60degree taper on the rear cones. Design is 4 baffles and an endcap to trap gasses along with a telescoping screw on mount (M22x1 threads).
The bore is aligned/indexed by the telescoping action sliding bearing surfaces over the exterior of the barrel - the barrel will have a finished surface to fit tightly on.
The baffle core will be plug welded into an inner tube. A clean serialized outer tube will be welded to the endcaps.
Materials will be all 304 Stainless because it's both readily machinable and weldable.

What should my material thicknesses be for the tubes and baffle faces?
As designed... my CAD program says the can will weigh something like 58.5 ounces (about 3.5lbs)!!!
I drew up the basic K-Baffles and tube - making them look like proportionally satisfactory, IMO.
The inner tube is .050" and the outer tube is 1/16" (.063"). The baffle part thicknesses vary from 3/32" (.094") to 1/8 (.125")
Should I replace the 3 end baffles with Aluminum?

tagged!


interesting design.

Well, it's not truely an inner wall like some cans have. What's really neat about this desig (IMO) is that the baffle faces are recessed into a machined in bore. I believe it can be all done manually.
Instead of cutting off the face of the baffle from the stock - cut it off with some distance left over and bore out the face to the OD of the Kbaffle skirt. Then contor the baffle face with a round toolbit.
Then make appropriate holes for plug welds or gaps for full circumference welds. What your left with are baffles that telescope into each other and are welded into place.
Then the outer tube provides more strength under high stress and is welded all around the endcaps.

However, I must've got my wall thickness proportions wrong or the made the baffles too beefy... because that's a pic of a 3.5# can.

Here is a picture of the baffle interface:

what type of metal are you using

Materials will be all 304 Stainless because it's both readily machinable and weldable.

;)

On a side note... I noticed I was using 1/4" thick baffle faces and 3/16" thick skirt walls.
I dropped the thicknesses of the two and kept the same proportions.
The thinnest part of the baffle face at the low point of the face-cut is 1/16" with about 3/16" thickness at the baffle face outer edges (the face cut is 1/8" deep).
The skirt on the rear of the baffle was reduced to 1/8" thick.
Both of these changes actually shortened each baffle by about .25" so the assembly can be about 1" shorter Then I made the outer tube .050" (similar to the inside "tube" thickness).

All in all, with 304 stainless construction, this brings the can's weight to about 44oz.
I could probably get it around 24oz if I use aluminum baffles, endcaps, and tube (leaving the blast chamber parts stainless).

What would a good weight for a 11"L x 1.75"D silencer be?
The AAC M4-1000 is 7.25 @ 19oz  so proportionally for a 11" suppressor the weight should be about 29oz... but mine also has a bigger OD and 2 more baffles.

I assume you already have your tax stamp or you are in the process of getting one.

What's a tax stamp?
Some sort of metal stamp for tube or baffle making?

Just kidding!

I am just in the planning stages for the .223 can. My lathe is arriving sometime this week (hopefully).
However, I am going to build thread assembled .22lr and 9mm suppressors before attempting a welded rifle caliber can. Work my way up, you know.
I already have the .22lr and 9mm cans designed and the machining operations laid out on paper.
Sometime between now and the start of the .223 build I hope to procure a TIG welder for the home shop.

Quoted: I assume you already have your tax stamp or you are in the process of getting one.

For what - a bunch of CAD drawings?

Quoted: Quoted: I assume you already have your tax stamp or you are in the process of getting one. For what - a bunch of CAD drawings?

The Thought Police have been alerted!!


Seriously though, I've always wanted to try what you are doing.  I missed my last chance to get a nice lathe on the cheap.  Now I'll have to seek one out.

Pneumagger,
Very nice design. Just food for thought. If I were building this one. I would use stainless in the main exp. chamber and maybe the last 2 baffles and end cap out of aluminum. You would have to thread the endcap in because you can not weld or tig stainless and Alu together. Also you may think about using Alu for the outer tubing with both ends being Alu, there for you would be able to put your internal peices in and then compress it together inside the Alu tubing and tig both endcaps on. Since you do not plan on using for full auto. The Alu will get hot if you just pull the trigger as fast as you can, but it will take at least 3 clips before things start to sag.hinking.gif
Again, just food for thought, and please please let us know how it works.
SGT King

I took alot of comments into consideration and will redesign it. I'll probably fire up the CAD tonight and model the revisions.

I actually decided to make baffles 2/3/4 out of aluminum and keep the blast baffle and blast chamber parts made out of SS.
Both endcaps and tube will be made out of SS too. I am going to do a stepped tube design after the blast chamber.

This will do 2 things:
Keep all the mounting hardware and tube more rigid and made out of the same material. This should give better concentricity under high heat.
Provide a positive seal as parts heat up. The aluminum will expand faster than the SS as it heats... so you don;t want stainless inside of aluminum.

I'll get a pic up after I get a model tossed together.

Don't use any aluminum for 223. it will not survive.  Typically, the blast baffle is Inconel or similiar as even stainless will look like a bad bead blasting job after a while.  Remaining baffles should be stainless.  Since you're using a two point mount, check out some of the Finnish designs as they're much simpler on the back end and that volume can be put to good use.

you could also do a muzzle device like the OPS brake to act as a primary blast baffle. this would take some of the punishment off of the blast baffle, and be easily replaced, rather than a welded part inside of your can. just a thought.

you could also do a muzzle device like the OPS brake to act as a primary blast baffle. this would take some of the punishment off of the blast baffle, and be easily replaced, rather than a welded part inside of your can. just a thought.

Bingo... the middle index threads on the rear of a Brake, the rear index wedges onto a contoured barrel, and the front index fits around the crown of the brake.

Don't use any aluminum for 223. it will not survive. Typically, the blast baffle is Inconel or similiar as even stainless will look like a bad bead blasting job after a while. Remaining baffles should be stainless. Since you're using a two point mount, check out some of the Finnish designs as they're much simpler on the back end and that volume can be put to good use.

Turning inconel on a benchtop lathe might be near impossible. Heck, I'm just hoping it handles 304 Stainless easily.

The can will have a stainless blast baffle and a a muzzle brake to take the hardest beating.
You don't think 3 Aluminum baffles would fair well sitting behind a brake and blast baffle in a stainless tube?
Doesn't the Tac 16 have aluminum baffles?
Would Titanium be a better choice?

Anyways, the design below is a tad bit lighter. It gets rid of the double tube and uses a stepped tube with a double tube around the blast chamber. It also lightens up the baffles a little.
The blast chamber tube is .050" and the outer tube is .065" - both made out of Stainless as well as the blast baffle, and both endcaps. This way the suppressor can be welded shut.
The blast chamber parts will all be fully welded and the endcaps will be welded onto the outer tube. K-baffles 2/3/4 will be aluminum.
OAL Length is 10.5" and Diameter is 1.750" with 6.25" length added to the host weapon.

If construction is 100% 304 Stainless the weight is 40oz.
If baffles 2/3/4 are aluminum 33oz.
For a 10.5" x 1.75" can I think 33oz-40oz is about as light as it's gonna get...
I mean, a proportionally weighted/sized AAC M4-1000 would weight about 30oz and this is just a form 1 can.

that new design looks quite a bit better. the weight savings will make the can much more enjoyable . Ti instead of Al will hold up better but the cost will be much higher . should be a quiet can at any rate .

Noob question: how much effect does having the portion behind the muzzle have on sound reduction? Or in other words, what is the purpose?
It's a very interesting design.

Quoted: Noob question: how much effect does having the portion behind the muzzle have on sound reduction? Or in other words, what is the purpose? It's a very interesting design.

www.reflexsuppressors.co.uk/


It's an old way of getting additional volume for gas expansion out of a suppressor without having to add additional length to a suppressor, keep the expanding gasses behind the bullet and allow them to cool more before entering the stacks of baffles.

Stay away from aluminum in any centerfire can.  Every manufacturer that uses aluminum in their rifle cans quickly switches to all-stainless designs as they realize how crappy aluminum is for centerfire rifles.

Titanium would be acceptable if you rarely plan to shoot rapidly.  Otherwise, stick to stainless.

Tagged for academic gains.
sw1217

I would try to lighten everything until you get down to 25-30 ounces or so. Don't change materials, just make the parts lighter. Your baffles are really thick, they can go on weight watchers and not lose effectiveness. It doesn't have to be as light as a Surefire can but a 3 pound 5.56 can just isn't going to be any fun.

Conquorer... after looking into it more even the TAC 16 is all steel. I guess I'll be following suit.

Quoted: I would try to lighten everything until you get down to 25-30 ounces or so. Don't change materials, just make the parts lighter. Your baffles are really thick, they can go on weight watchers and not lose effectiveness. It doesn't have to be as light as a Surefire can but a 3 pound 5.56 can just isn't going to be any fun.

Even the redisnigned picture's baffles?
How thin can I make my baffles without them collapsing?
Should I thin out the rear skirt or the baffle face?
Fluid pressure forces are not something something I can readily calculate so I don't want to make my baffles lighter untill I just arrive at an arbitrary weight.

I know I don't want to go below 1/16" (.0625") on the full length outer tube and .050" on the blast chamber reinforcing tube.
I know I really want 4 baffles for trapping gasses (YHM uses 3 and the AAC M4-1k/2k uses 2) and I know I want a larger diameter (1.75") for more volume too...
So those qualities I want are going to make my can weigh more than most commercial cans out there.
Because of the larger than normal diameter, extra baffle, and reflex... I think a goal of 35oz is both safe and enjoyable.

My other option is to go with a traditional thread mount... which brings an all-SS construction down to ~37 (2.33lbs).
But the length added to muzzle increases, so the weight savings may be offset by a can that "feels heavier" hanging out front.