Sound Attenuator/Baffle

[WayneShaw]

Looking for ideas to help keep down some of the noise at the shooting bench. I want to keep the neighbors happy before it's a problem.

I was thinking about simply using a 55 gallon drum, cut out the top and bottom but leave about a 6' 'baffle' ring around the perimeter. Line the inside with shag carpet, then mount it horizontally right up against the bench so the muzzle would be into it a little.

I know I can't stop it all, but hopefully cut down on the sound travel some. And not disrupt or effect groups!

 

[GLZ]

I remember a gun writer doing something similar. He used rolled up expanded metal through the center of the drum and packed between the drum and expanded metal with steel shavings from a local machine shop. You could use loose fiberglass insulation also,think glass pack muffler)

 

[BoydAllen]

http://www.soundrite-acoustics.com/

 

[cliffe]

my buddy and i were talking on making something similar. we had discussed using old tires bolted together sidewall to sidewall. i would think that rubber would work good to deaden the sound. you could stack 5 or 10 tires together and see if would work.
i read somewhere that someone used fiberglass insulation held out by chicken wire and that the insulation would blow out from the muzzle blast.
i also wonder how carpet foam would work to deaden the noise, instead of the fiberglass insulation. hopefully we will see some innovative designs brought forth. cliffe

 

[jlmurphy]

I remember that article, I think it was Rick Jamison, a tech writer for one of the rifle mags in the 90's. He had a workshop with a bench set up against a roll up door, outside the door were 3 or 4 steel drums forming a tube, and I recall it was steel cuttings of some kind. I think the tire idea is better, you could place steel or wood discs between each tire with a smaller hole in the center.

 

[Travelor]

Think of it as a big silencer - a tube with baffles. I like the tire idea much better than steel drums as the drums would probably resonate. If were me, I would use the tires with a small opening at the rear,just enough to get the barrel though and allow the scope to 'see') with curtains of rubber,or a similar sound 'de-resonating' material with slightly larger holes at each tire and a small hole at the front.

Just be sure to put the muzzle of the gun into the first baffle before firing.

I helped build a plywood box with fiberglass insulation held in with chicken wire for a friend that shoots pistol. The box is 8 feet long and three feet square with 12 inch square openings on each end. We suspending it from the ceiling of a pole barn roof with cables and pulleys so that it could be adjusted for different height shooters. It is HEAVY! The fiberglass does not come out of the sides when firing, but the large openings do not reduce the sound much either. Remember this was with a pistol - 22 LR and 38 Special only.

 

[cliffe]

i took some 17' rear sportbike and bolted them together top and bottom. these tires are about 7' wide, i bolted 5 of them together for about 3 feet long. next week i'll have some time to fire a few rounds and i also have a decibel meter, so i will post some results as to what type of noise reduction i came up with. also am going to try a few extra for length and a smaller end tire. cliffe

 

[WayneShaw]

I appreciate the responses. I'll play around with a couple ideas and see/hear how things go.

I know I can't stop all the sound, but if I can tone it down quite a bit, hopefully the neighbors will be happier.

 

[cliffe]

i bolted together 5 sportbike tires, 17' dia. about 7' wide sidewall to sidewall, about 36' in length. shot a ruger 10/22 through it and it was louder than without both for the shooter and the guy off to the side with the d.b. meter.
put a rolled up egg crate open cell bed mat in it and it was as loud as the regular gun without anything, maybe a one d.b. quieter, but was louder for the shooter.
back to the drawing board.....cliffe
p.s. buddy said if it was possible wouldn't they have them in all indoor ranges.

 

[infantrytrophy]

Check out these pictures of the ultimate reloading room and its attached shooting tunnel with sound baffle:

sound baffle/reloading room

 

[cliffe]

infantrytrophy, i tried egg crate foam material inside the tires and dropped maybe a decibel from what it was with nothing.what type of noise reduction do they claim. i was thinking on putting a large cardboard box with a smaller opening on the out side next. will also try longer too. cliffe