My last post meandered a bit, so let me start with images of the directional reducing diffuser concept muffler. It does
not have any features to protect the shooter from increased rearward blast (yet). The vents pointing back in the last row are at 45 degrees beyond pure radial. So, nasty for the shooter's ears in this concept design. The inside "tube" and front outside edges of those vents will reflect sound back at an even shallower angle, so any implementation of the idea is screaming for help to shield the shooter's ears - coming later.
Also, the ability to print the part standing on its front end will need to be restored via external supports. (Or a cylindrical design that has a swept hole pattern) Printing with the mounting thread down will collapse the internal cones; so that is not viable.
Anyway, consider this design purely as a goal statement, to spread the sound spherically, to make the sound less directional.
The vent holes are 2.5 mm in diameter as shown, but should print closer to 2 mm when FDM is used.
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