Bench top “sound deadening” box

[Uglyjohn]

OK some time ago I saw where a guy made one of these and I think it was on AGN. It amounted to a box with the sides lined with foam or carpet or some other sound deadening material. The center was open allowing it to be shot thru with substantial sound reduction. My search didn’t find the post so I’m asking if anyone else saw it or has made and used anything like it. Uj

 

[Redick]

I believe they use rubber mulch or similar material purchased at Home Depot or Lowe's 

 

[JCD]

Could have been 'unrepentantsinner' on the old yellow? I think i got the name right. He had just what you are describing on his porch overlooking the vineyard he lived at. Simple 4 sided 3ish foot long box that was open on both ends with something that looked like oversized eggcrate foam lining the interior.walls. I took a quick look on the old yellow and didn't see any posts where he described it, but I only looked for 30 seconds... 

 

[LessMundane]

"When things need to be very quiet around the house, try a sound reduction box" is the thread title started by Roachcreek.

 

[sturba]

Not exactly bench top yet, but if it’s late and you need some numbers..

10” insulated attic ducting from lowes

should mention, bayonet style chronograph in this case

use your own throw pillows

 

[Bigragu]

If I needed it to be dead quiet for testing purposes I would rig up a set up shooting into a rubber mulch trap but first shoot thru a 4” diesel exhaust muffler that’s mounted directly into that trap. If you go to your local junk yard I’m sure there’ll be a straight thru muffler in the yard somewhere.

Dont know for sure it works as getting things dead quiet, but if it were me, that’s what I’d try first.

my next option would be to make a long rectangular wood frame box lined on the inside with drop ceiling T bar tile, the acoustic type used in movie theaters and Sound rooms. Again, shoot thru this and this framed box is connected to the pellet trap.

 

[Darren]

OK some time ago I saw where a guy made one of these and I think it was on AGN. It amounted to a box with the sides lined with foam or carpet or some other sound deadening material. The center was open allowing it to be shot thru with substantial sound reduction. My search didn’t find the post so I’m asking if anyone else saw it or has made and used anything like it. Uj

Are these the ones your after John??

 

[GBGUNNER]

I have seen one built out of 13'' car tires stood up and bolted together to form a hollow "tunnel" then placed fiberglass attic insulation stuffed into the tires and he fired a PB rifle through it to deadening the report and he didn't use hearing protection. The tunnel could be made from sonotube (for forming vertical columns of cement) from the lumber yard and forming a wire tube from 1/2" hardware cloth/ screen and support it inside the sonotube to center it inside the sonotube with 3 pieces if wire at the front and back. Then fill the space BETWEEN the sonotube and the wire screen tube with fiberglass insulation. The wire screen tube needs a diameter large enough to allow your line of site and line of pellet to both pass through the " sound deadening tube" without striking the screen. do not use window screen. So you end up with the 1/2" hardware cloth wire screen tube running down the center of the heavy duty cardboard sonotube with fiberglass insulation in the space between the wire screen tube and the sonotube. I would use 14" or larger sonotube and a 5'' -6" diameter hardware cloth tube and non backed fiberglass bat house insulation. The sonotube should last a long time in the weather, but if you cover it and the open ends with a tarp to keep wind,rain, snow, birds, etc out it will last. Experiment with placing the muzzle 6" to 12" into the wire tube for best results

 

[Uglyjohn]

Bingo Darren that’s the one! I have a gun that I’d like to shoot at home. Problem is that it has an air stripper more or less permanently attached and it’s too loud. A simplified version of the box shown just might be the answer. Thanks for this and all other responses. Uj

 

[Michigander]

Here was my attempt. I originally hoped to use it for centerfire, but it didn't do much. But it does work for air rifles indoors if that is what you are looking for. It is just a simple box made of OSB. I tested it with and without padding and got these results.



So the padded box reduced the noise by 12 dB, and since a reduction of 6 dB cuts the sound pressure in half, both Max and peak noise were reduced to about 1/4 their former values. For the test I just used old towels for padding the inside. Some combination of heavy felt and acoustic foam might work even better. The box dimensions are 28" X 11" X 9"W. I don't know if I made it bigger than it really needed to be or not. I am pretty sure that keeping the size of the openings as small as practical helps considerably to contain the noise.