AusVarmint

I have been building a box to shoot through, with the idea to keep the wife happy when I fire my rifles in the back yard.
I live on a farm so this is not a problem but it scares the shit out of her if I forget to tell her what I am up too.
Even then she complains about the noise. No pleasing some women.
Anyway I hope this device keeps the noise down, I will let you know how it goes once I christen it in a week or so.

The sides are three inches thick and filled with foam. It has three chambers, a blast chamber, a smaller buffer chamber with sliding doors to reduce the noise coming back towards the shooter and an exit chamber full of egg cartons to dampen down the noise towards the target. The top lid will be removable to enable changes and modifications as needed.
It will have wheels installed to help move it about as it is getting a bit heavy.

If you can think of any way to make improvements please let me know.

Bloody good idea if it works! not really practical for shooting ferals but ideal for sighting in, load development etc. Don't be shy and tell us how it goes!

It would work better if you left the eggs in the cartons.

Chiller panels would have been the go i reckon already insulated and basically noise proof.

G'day Wadcutter,

Looks good but have you contemplated ventilation and a light?

Regards

Sean

I think you will have some success, but would be interested in more information about the rifles your using.

Assuming that they are .223 to.308 types would mean
1. Some noise deading of the boom as the large volumes of gases all try to escape behind the projectile,
2. No change to the sonic crack that will occur as the bullet breaks the sound barrier.

Understand that your looking to keep costs low, but adding as much material over the plywood base would only add to the deading of the boom.

Interested to hear how it works out for you. Good luck.

My wife said she would like to put me in it and screw the lid on tight. At least if the eggs where still in the cartons I would have something to eat!

I intend to fire a variety of rifles through it. .222, .25-06, .30-06, .338WM, .458WM and my new .338Edge.
Don't know how the Edge will go as it has a large side port brake on it that will deflect gas right into the side of the box.
The box has 2" of foam between 2 plywood sheets on both sides and the floor plus rubber stuck to the inside. The top will have just hight density foam and rubber stuck to the 5 ply sheet.
Also thinking of sticking a thick peice of foam above where the barrel goes just to protect it .

You can buy a paintable sound deadener from most automotive shops.

Perhaps if this was applied underneath the egg cartons it may assist somewhat.

Regards

Sean

oh my god, your making a silencer! i'm calling the cops!

wouldn't it be easier to buy her some ear muffs and a gag?

P

ogre6br wrote:wouldn't it be easier to buy her some ear muffs and a gag?

P

Probably more beneficial to encourage her and get involved in the sport

Regards

Sean

Sean Ambrose wrote:Probably more beneficial to encourage her and get involved in the sport

Regards

Sean

No way,
I tried that once and she outshot me.
She reminds me of this every now and then, just to put me back in my place.

wadcutter wrote: No way, I tried that once and she outshot me.
She reminds me of this every now and then, just to put me back in my place.

Yes, I must confess my @rse has become grass since I introduced Leanne to the sport.

She now shoots 200.15+ consecutively week in week out and we are now down to counting center X ers. She out shot me again last night (in worse conditions during the storm).

It can be quiet stressful at times.

Regards

Sean

many moons ago I studied sound engineering and part of syllabus was studio design and soundproofing so here goes..

for one.. I don't think any box will be able to deaden the sonic boom unless it is totally sealed which is obviously not possible here.. but here goes..

try and find yourself a material called rockwool.. a large musical instrument place should be able to lead you in the right direction.. get rid of the foam in the side panels and fill it with the rock wool..

I also think the muzzle blast is going to destroy those egg cartons pretty quick.. something more robust and less ridgid and thin is going to be needed... perhaps a cheap alternative would be eggshell foam in the 50mm variety - available at Clark Rubber

Is the lid you are using insulated as well... because I feel if it is not, you are going to get some interesting reverberation in that box.. think "fully sick subwoofer"..

you will also need to cover all the ply in the box with your choice of soundproofing.. in this case egg cartons.. the dividers that are not covered are also going to reflect the sound quite a bit - again subwoofer box..

I reckon it will dampen the sound, however, you wil find that with the box not being sealed, all you will be doing is redirecting the sound .. any chance you can make those divider/baffles larger.. i.e. the holes in the middle of them smaller..

interesting project though.. I once helped a mate build a soundproof box for a very noisy generator.. sealed box, fans and baffled exhaust/intake ports.. for 2mt away you could not hear it

let us know if you need anymore advice or a head to bounce some ideas off..