sound-muffling chamber for indoor range?

[M-Cameron]

Interesting, thanks! Looks to be basically just plywood boxes? Maybe some rubber floor mat inside?

from the video, that looks like about all there is to it.....

looks like they have a plywood box, a layer of insulation, and then some peg board to act as some sort of 'porting' or 'baffles'

 

[Carl N. Brown]

"the tube of tires" type sound muffler attached to a shooting stand does not meet the 1934 NFA description of a silencer (attached to the gun) and is legal, since it is more likely to be used shooting at range, than to be used with the gun as a weapon.

 

[PBR Streetgang]

we had approxamately 30 tires bound together and a shooting bench at the end. It did a nice job of killing the sound from the shooters area....only one person could shoot at a time....and it was a bit tough retreiving the spent brass from some of the autos that tossed their empties forward....water laying in the bottom of the tires made a great mosquito breeding ground!

 

[Mike1234567]

^^^ Drill small holes in the bottom of the tires... unless you think using the suppressor wet helps further reduce noise.