What is wrong with this K-Baffle design?

[mcrump]

I am extremely disappointed with this design. I can detect no sound reduction whatsoever.

Cal 22
OD 1.0
Wall .065
Length 6.0

Well, I would post a picture but I can't find the "Upload" button.

[ghostdog662]

You need to use an image hosting service like photobucket or imgur.

Then click the img button and enter the url to that image.

[mcrump]

Ghost,

Exactly where do I stick the link? Is it between the brackets [img] like here [\img]?

[mr fixit]

Ghost,

Exactly where do I stick the link? Is it between the brackets [img] like here [\img]?

yes

[mr fixit]

Saw it the first time before you edited the link away. Here you go:

[ghostdog662]

This is how you should try to make your baffle.

[MartinDWhite]

What is your expectation for sound reduction?
What weapon and ammo are you using?

[mcrump]

Walther P22, Subsonic ammo.

I would at least like it a little quieter than it is now. As I said, I can't really tell the difference between suppressed and unsuppressed with this design.

Are there any basic dimensions for the above baffles? Or a drawing?

Thanks!

[a_canadian]

You'll want about twice as many baffles in the same length, that's the main thing wrong with this stack. Long K baffles suck in my experience. Keep them short, mill the vents deep enough for excellent cross-flow, scoop the faces deeply, and all should be good. You can probably get at least 8 shorter baffles in there.

[T-Rex]

Start here and redesign as you wish

[mcrump]

Are the mouse holes drilled or milled at an angle? If drilled, what size diameter? If milled, a ball end mill or flat face?

Thank you for the info.

[a_canadian]

Most use a ball end mill, same diameter as the baffle bore. But if you have something pointier that's probably okay. A flat faced mill is sometimes used but I doubt the flow is nearly as efficient. A drill? Meh, sure, if it's all you have, but keep it short so as to control the cut.

[gunny50]

Saw it the first time before you edited the link away. Here you go:

I do guess that the K with the long neck is your blast baffle, if so port the neck with drilled holes so gas will lead of into the space beween neck and wall.
It will help you get better reduction.

Gunny

[T-Rex]

Are the mouse holes drilled or milled at an angle? If drilled, what size diameter? If milled, a ball end mill or flat face?

Thank you for the info.

Most use a ball end mill, same diameter as the baffle bore. But if you have something pointier that's probably okay. A flat faced mill is sometimes used but I doubt the flow is nearly as efficient. A drill? Meh, sure, if it's all you have, but keep it short so as to control the cut.

Are drill bit can be profiled to mimic a ball end mill.
Profile and material will determine its effectiveness.

[a_canadian]

Looking again at the baffles, my guess is that the biggest problem isn't the length (though of course they're way too long and that long-necked baffle is kind of comical as a waste of tube space), but the porting. The sharp rectilinear end of the cut in the cone bothered me... until I realised you'd drilled it out from the back side, using one flat-ended mill bit to cut right through both ports. That means your face port makes the bore oval shaped, which means it accomplishes nothing at all since the fast-moving gases aren't even going to go there. You need to cut the vents from each end, not both at once. They can be pretty close to identical in terms of mill placement but they need to leave the bore hole alone, not open it out sideways. Your goal is to strip away as much pressure/gas as possible. You're not going to do that by getting the baffle edges out of the way. That's almost as bad as drilling a much too large hole down the middle of the stack.

[mcrump]

Thanks for the reply. Yes, I drilled thru both surfaces. My mistake. I will use a ball end mill and mill from both directions. As for alignment in the tube, should the mouse holes be in alignment, in opposition, or in random alignment?

[T-Rex]

Of all the many manufacturers, they're is no one direction.
Just swap yours around and take note of the changes, if any.

[a_canadian]

There's a substantial majority who say that 180 degree alternating is the way to go for a .22lr can, but a substantial minority who believe they should all line up. You can always try it each way and see, since it's unlikely your baffles will be locked into position.

As for 'mouse holes' that can be problematic, as many would have it that the vents you've cut into the big ends of the cones are called mouse holes. Terminology is another place where there isn't quite consensus, so mouse holes get thrown around meaning as many as three different things, the other being the Dater hole in the first baffle face.

[Capt. Link.]

Follow G-dogs design as close as possible.Don't add any mouse holes in the conical skirt.The porting is done as a straight plunge cut with a center-cutting ball end mill from each side.The gas port into the coaxial chamber is small.Line up the ports and use a Dater hole in the blast baffle 180* out from face port.

If this is a form 1 all you can do is modify what you have.

-CL