Monolithic baffle stack

mpallett · Post by **mpallett** » Fri Dec 21, 2007 5:58 pm

GaLEO wrote:mmmm, Matthew, that seems like a question you already know the answer too..

Nope ... I have drawings from like 10 years ago for a design like that, I just never got around to trying it.

HotGuns · Post by **HotGuns** » Fri Dec 21, 2007 6:03 pm

Great job Baffled...

glad to hear that it worked out. Its been a very interesting read.

Mtdew · Post by **Mtdew** » Fri Dec 21, 2007 6:57 pm

Baffled wrote:Further update: I had a chance to compare this can to another F1 can. This can was slightly larger, and had a very elaborate and complex Omega-style baffle stack which was executed very well. This new staggered monostack was distictly quieter. It wasn't even close. I don't say that to blow my own horn, because the concept is not mine. I have nothing to prove and no agenda. Guys, this stack works. I don't know how sensitive it is to variations in the mouse holes or to dimensions... hopefully, not much.

FWIW, this stack is 1.250" dia X 7.2" long. The holes are 3/4", spaced 0.750" along the X-axis, and offset from the centerline 0.156". The annular cuts were made with the same 3/4" end mill, plunging into the stock for a distance of 0.220" from first contact; OR +/- 0.781" right and left of the centerline.

I'd love to see another one executed to see if this is not a fluke.

Did you end up porting both sides? The way i'm reading your other post it seems like you just did the one side

bakerjw · Post by **bakerjw** » Fri Dec 21, 2007 7:29 pm

I can say that my next can may be of this design. Great feedback on what you built.

CS223 · Post by **CS223** » Sat Dec 22, 2007 6:34 am

Check out Griffin Armaments Checkmate mono design.

Opps, ETA this was mentioned on pg 1

Paledaddy · Post by **Paledaddy** » Sat Dec 22, 2007 8:13 am

What about this type for a 223 can

Pd

Baffled · Post by **Baffled** » Sat Dec 22, 2007 8:47 am

Mtdew wrote: Did you end up porting both sides? The way i'm reading your other post it seems like you just did the one side

I did just one side in its entirety, then tested it. When I heard almost zero FRP and an overall suppression that got me very excited, I said to myself "DO NOT touch it again. Nothing more to be gained." So yes, it has just one set of mouse holes. On my first F1 can, the more I jerked with it towards the end, the louder it got. I don't want to repeat that.

A couple of things which may be helping... the muzzle of the barrel is almost in contact with the stack itself. There is perhaps 0.016" clearance so that when the can is screwed on, it bottoms on the shoulder of the barrel, as it should, rather than the threads. So the bullet exits the bbl and immediately enters chamber #1, which I sleeved with a steel ring, not shown in any of these pictures. The steel ring has a wall of maybe 0.040", so the first chamber is slightly smaller than subsequent.

The aluminum "wall/baffle" thickness between the chambers is pretty thin. That too may be helping things. Clearance between stack and tube wall is about 0.015" all around.

When I parkerize the tube and endcaps, I'll take some final pictures.

CS223 · Post by **CS223** » Sat Dec 22, 2007 9:41 am

Baffled wrote: I drilled a series of mouse holes on one flank only for now, 3/16", oriented in such a way as to proceed from the peripheral cuts and from there, BARELY contacting the bore hole.

Did you add the mouse holes from the bore hole to the peripheral cut forward of the bore hole or to peripheral cut preceeding the bore hole?

Baffled · Post by **Baffled** » Sat Dec 22, 2007 1:57 pm

Some more pics, prior to finishing:

Here is the side of the stack with the mouse holes. The path of the bullet is from RIGHT TO LEFT. Since only one side is drilled, only half of the inner chambers have mouse holes.

A bit closer:

The chamber far right is the first, and takes most of the blast. You can see the steel sleeve and the securing roll pin. The blue line represents the angle of the drilling. When drilled from outside towards the bore, the drill breaks out just above the bore hole. The theory here is that the gasses, at high pressure at the bottom of the circled cut, swirl forward and up, and are ejected forward and thru the mouse hole. In the chamber far left, you can BARELY see the pattern of the bore hole, and the mouse hole.

The test rig: AR15, DIAS, Ciener, 10" Kuehl

Post by **silencertalk** » Sat Dec 22, 2007 2:25 pm

STW has a patent on monolithic baffle cores which employ 'cross drilling.' I have not read it in a while but I think this would fall under that. I know when I did the Prodigy I made sure not to just drill holes.

HotGuns · Post by **HotGuns** » Sat Dec 22, 2007 4:18 pm

I had a thought...

since the holes are off center in relationship tp the bore in which the bullet passes through...that causes the gas to spin up wards when the hole in on the bottom and down wards when the hole is on the top. When you drilled the holes on the top of the stack, since the gas is circling that way it bleeds off the gas and effectively increases the volume.

I think that if the same thing were done for the bottom that it would do exactly the same thing and increase the volume even more.

It would be interesting to see you test it with holes drilled on the bottom. since you already have a baseline to go by. It wouldn't be hard to do, and we would know for sure if the bottom, holes were worth drilling or not.

What'd ya think ?

Paledaddy · Post by **Paledaddy** » Sat Dec 22, 2007 5:02 pm

HotGuns wrote:I had a thought...

since the holes are off center in relationship tp the bore in which the bullet passes through...that causes the gas to spin up wards when the hole in on the bottom and down wards when the hole is on the top. When you drilled the holes on the top of the stack, since the gas is circling that way it bleeds off the gas and effectively increases the volume.

I think that if the same thing were done for the bottom that it would do exactly the same thing and increase the volume even more.

It would be interesting to see you test it with holes drilled on the bottom. since you already have a baseline to go by. It wouldn't be hard to do, and we would know for sure if the bottom, holes were worth drilling or not.

What'd ya think ?

Well offcourse it will be better with the bottom half also drilled !!

Cant be nothing rong with doing that

Pd

CS223 · Post by **CS223** » Sat Dec 22, 2007 7:07 pm

rsilvers wrote:STW has a patent on monolithic baffle cores which employ 'cross drilling.' I have not read it in a while but I think this would fall under that. I know when I did the Prodigy I made sure not to just drill holes.

I checked the patents (did not read them in depth) by Carl L. O'Quinn & Raymond W. Andrews Jr. who apparently own STW and did not see anything that resembed Baffled's design or the Prodigy, specifically the 'mouse holes'. Perhaps it was another patent?

Post by **silencertalk** » Sat Dec 22, 2007 8:38 pm

http://www.google.com/patents?id=EB4DAA ... dq=6079311

1. A noise and recoil suppressor for firearms comprising a bullet entry end, a bullet exit end, and a cylindrical body having a plurality of chambers extending transversely therethrough so as to define a dividing wall between adjacent chambers that are spaced along the longitudinal direction of said cylindrical body, said bullet entry end and exit end and said dividing walls having apertures therein through which a bullet and exhausting gases can pass, said plurality of chambers being shaped so as to slow passage of the exhausting gases therethrough and thereby suppress noise at the bullet exit end of said cylindrical body, and said plurality of chambers being formed in said cylindrical body by cross-drilling said cylindrical body.

HandyMan · Post by **HandyMan** » Sat Dec 22, 2007 9:06 pm

rsilvers wrote:http://www.google.com/patents?id=EB4DAA ... dq=6079311

1. A noise and recoil suppressor for firearms comprising a bullet entry end, a bullet exit end, and a cylindrical body having a plurality of chambers extending transversely therethrough so as to define a dividing wall between adjacent chambers that are spaced along the longitudinal direction of said cylindrical body, said bullet entry end and exit end and said dividing walls having apertures therein through which a bullet and exhausting gases can pass, said plurality of chambers being shaped so as to slow passage of the exhausting gases therethrough and thereby suppress noise at the bullet exit end of said cylindrical body, and said plurality of chambers being formed in said cylindrical body by cross-drilling said cylindrical body.

Looks like the pictures in the Patent application show the chambers also have milling cuts. If the patent claims were that broad, even the Prodigy would be covered.

I thought the STW patents covered in the barrel modules. The stack Baffled built is for a detachable muzzle can. Does STW have a patent that covers a detachable suppressor?

CS223 · Post by **CS223** » Sat Dec 22, 2007 9:35 pm

rsilvers wrote:http://www.google.com/patents?id=EB4DAA ... dq=6079311

1. A noise and recoil suppressor for firearms comprising a bullet entry end, a bullet exit end, and a cylindrical body having a plurality of chambers extending transversely therethrough so as to define a dividing wall between adjacent chambers that are spaced along the longitudinal direction of said cylindrical body, said bullet entry end and exit end and said dividing walls having apertures therein through which a bullet and exhausting gases can pass, said plurality of chambers being shaped so as to slow passage of the exhausting gases therethrough and thereby suppress noise at the bullet exit end of said cylindrical body, and said plurality of chambers being formed in said cylindrical body by cross-drilling said cylindrical body.

I've read that section of the patent. They specifically refer to a T shaped chamber when viewed in side elevation. Cross drilling is just the method they used to describe their machining operation. Milling would accomplish the same thing. All of O'Quinn's patents have singular chambers, none have secondary or coaxial style chambers seperate from the boreline like the Prodigy or Baffled's design. In addition, both the Prodigy and Baffled's design have the mouse hole perpendicular to the bore axis. All of O'Quinn's designs are parallel to the side elevation & bore line and none of O'Quinn's designs have secondary chambers. But I'm no patent expert.

Now if you want to challenge the Griffin Armament Checkmate design, I think you will find it closely & better resembles another one of Carl O'Quinn's designs.

http://www.google.com/patents?id=fbsGAA ... +O%27Quinn

HotGuns · Post by **HotGuns** » Sat Dec 22, 2007 10:11 pm

What difference does it make?

As long as you dont try to go commercial with it, it shouldnt be an issue.

CS223 · Post by **CS223** » Sat Dec 22, 2007 10:31 pm

HotGuns wrote:What difference does it make?

As long as you dont try to go commercial with it, it shouldnt be an issue.

It's just a finer point of discussion worthy of clarification. If it were a patent infringment, Baffled and ST legally could be required to kill this thread and cease desimination of the information. RS has a lot of time invested in the study of various patents and I value his objective commentary and I'm trying to understand his point of view. I have no interest in pissing matches and refuse to participate in such.

cocoboots · Post by **cocoboots** » Sun Dec 23, 2007 1:00 am

it doesn't matter if you build it for yourself or build it for commercial sale...it still infringes on a patent

i bet if someone posted a picture of a homemade "prodigy" mr. silvers would be speaking to them asap.

HotGuns · Post by **HotGuns** » Sun Dec 23, 2007 1:09 am

on the other hand...if it isnt exactly like the patent it is not infringement.

paco ramirez · Post by **paco ramirez** » Sun Dec 23, 2007 1:34 am

cocoboots wrote:it doesn't matter if you build it for yourself or build it for commercial sale...it still infringes on a patent

i bet if someone posted a picture of a homemade "prodigy" mr. silvers would be speaking to them asap.

Far as I know, Hyposone Tech is patent pending, not patented. IIRC someone did make something like it somewhere around here. Might ahve been Arfcom.

Post by **silencertalk** » Sun Dec 23, 2007 4:37 am

HotGuns wrote:on the other hand...if it isnt exactly like the patent it is not infringement.

Not true. STW 'owns' the manufacturing method of cross-drilling. I see that as a simple manufacturing method. The can in this thread could still be made, as long as you don't drill straight through. You would have to mill it out with a smaller bit that oscillated in circles and cut sideways.

Post by **silencertalk** » Sun Dec 23, 2007 4:41 am

HandyMan wrote: Looks like the pictures in the Patent application show the chambers also have milling cuts. If the patent claims were that broad, even the Prodigy would be covered.

What the pictures show does not matter. All you need to do is read the exact words of the claim-1. The further claims further define the invention, but the claim-1 is the most broad that was allowed by the examiner. The Prodigy is not manufactured by cross-drilling by design with this patent in mind.

I thought the STW patents covered in the barrel modules. The stack Baffled built is for a detachable muzzle can. Does STW have a patent that covers a detachable suppressor?

The claim-1 does not say anything about barrel module.

Post by **silencertalk** » Sun Dec 23, 2007 4:44 am

CS223 wrote:
I've read that section of the patent. They specifically refer to a T shaped chamber when viewed in side elevation. Cross drilling is just the method they used to describe their machining operation. Milling would accomplish the same thing. All of O'Quinn's patents have singular chambers, none have secondary or coaxial style chambers seperate from the boreline like the Prodigy or Baffled's design. In addition, both the Prodigy and Baffled's design have the mouse hole perpendicular to the bore axis. All of O'Quinn's designs are parallel to the side elevation & bore line and none of O'Quinn's designs have secondary chambers. But I'm no patent expert.

All irrelevant. The claim-1 is the most broad, and because it does not mention those, it is not limited to what is in the photos. You simply cannot make a silencer by cross-drilling without violating this patent.

Post by **silencertalk** » Sun Dec 23, 2007 4:45 am

HotGuns wrote:What difference does it make?

As long as you dont try to go commercial with it, it shouldnt be an issue.

You cannot even make one for home use if it is patented. As I said there is a way to make the silencer in this thread which does not violate the patent but it would take longer and would probably require CNC.