Don Walsh On Mesh In Suppressor Design

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Don Walsh On Mesh In Suppressor Design

Post by Historian » Fri Oct 30, 2020 11:13 pm

A long 'lost' article that has interesting insights by Don Walsh
one of the 1970s suppressor pioneers:

<< ... y_djvu.txt >>

Some might find interesting and glean design ideas.


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Re: Don Walsh On Mesh In Suppressor Design

Post by ninoslavt » Wed Nov 04, 2020 4:06 am

I don't remember the whole story, but Don Walsh actually lied about his designs (at least, it was not a fully truth) because he wanted to screw some guys who copied his suppressors. Sure thing, it was back then when everything suppressor/silencer related was so hush, hush so it was possible to fool someone.
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Re: Don Walsh On Mesh In Suppressor Design

Post by whiterussian1974 » Fri Nov 20, 2020 4:39 am

I read through most of the Link.

Mainly I got that he used mesh for Integral designs to wrap around the barrel porting.

Was there another section which I missed?

It's unfortunate that the pictures were missing from the text.
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Re: Don Walsh On Mesh In Suppressor Design

Post by Historian » Fri Nov 20, 2020 10:52 am

Hello WR, long time hearing your wisdom.

Donald Walsh's patent number is EP0107273A1 for his unique silencer.

Under the aegis 'he who publishes first gets the credit' I smiled when
it came out. As Newton and Leibniz they both came up with calculus about
the same time ... and thank goodness the Leibniz notation won out.

In past months of culling and shredding I found an un-submitted
patent application parallel to Don's approach that never got sent in due
to, shall we say, more pressing exigencies in the world in early 1980s.

Each approach solved the problem attendant all cans in the area of aligning the
end cap and inner baffles. The solution taken was to replace baffles with a central core
that extended from the end of the muzzle, with wider I.D..

Self alignment. Mis-alignment of baffles and end cap and off concentricity made irrelevant.

Don drilled out release holes, much in line with the idea of porting weapon's
barrel to reduce projectile's velocity prior to exiting barrel. Half of his holes
angled back, the others angled forward. This can be seen in patent drawing.

My TWIST ( pun definitely intended ) was inspired from seeing in 1965 in UK
Parker Hale concept can MK1 with no baffles, just inner snorkel and later
this concept implemented in the South African can as seen in Parker's book.
The whole can became the blast chamber. The PH can was noisy and did need
to be stuffed with some wire. Twist Gas Defuser.

Where Don had a solid self-aligning tube, my design milled a double spiral
twisted groove ⅓ of the length from the muzzle end. The integrity of the
single rigid structure was kept and gases swirled out turbulently into the can.

My fillip was to add a concentric spool of perforated thin wall steel, akin
to motor cycle tubing, between central core and outer wall, filled with
copper or steel mesh.

The write-up gave an example for .22 rimfire, as this was to be intended to
give an improvement to the HD OSS suppressor in certain operational

"Central self aligning tube 8". Outer wall 1.725". Average inner volume ~19 cubic inches.
[ Most rimfire cans in 5-6" range volume 4 cubic inches.]. etc

The rewards of addressing real world issues at that time far outweighed adding another innocuous

Again, wonderful hearing from you.

Very Best.

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Re: Don Walsh On Mesh In Suppressor Design

Post by Capt. Link. » Fri Nov 20, 2020 5:17 pm

Don's Patent is full of miss-information, his lawyer deserves a award for cryptic inventive writing and drawing.The use of mesh is mostly a ruse and was not used in production. The holes in the core do not affect velocity and do not point as depicted. A better description of this design would be a multiple coaxial segmented suppressor using a structural perforated core.
I peeked inside one of his "wonders". Lots of experimentation and much tuning went into the design. Precision is a understatement as the bore of these do not kiss the bullet.I suspect the tube perforations and segmented sections has as much to do with preventing bullet yaw as suppression with the tight bore used. Don gets the blue ribbon for thinking outside the box. I use a variation of his design to replace mesh in ported integral builds.
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Re: Don Walsh On Mesh In Suppressor Design

Post by Historian » Sat Nov 21, 2020 1:22 pm

The Good Captain's knowledge base always inspires.
Thank you.

I found an interesting PhD. thesis that some might find instructive.

"Investigations into the Optimisation of Sound Suppressor Geometry"
-Aimée Lister
Academic Year 2006 – 2007

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