Thread: Indoor range

Question for those with a scientific mind. Could probably find on the net but probably quicker here. A friend is looking at building an indoor range off a 100yrds to mitigate noise. He has out door ranges already. We've looked at concrete pipes and ppe etc but very expensive. also containers end to end but transport kills them. My question is that when a bullet breaks the sound barrier how long/far does that shock wave of noise travel? In other words could you say maybe use two or three containers as baffles with baffles inside like a giant suppressor with a small opening on the last. Would that contain the sonic boom and the bullet could then travel on happily to the target with little more than a muffled sound? Or would you have to have it contained all the way? We can bury containers or what we use to make that side of it very sound proof.
Interested in what you guys think or have done

Sounds like fun.

If you shoot from a container etc, with a small opening that the bullet exits from and onto the distant target... Remember your field of vision will be extremely small and there will always be a risk of someone walking in front of that opening at the wrong time.
A six foot electric fence with lots of warning signage and a range flag might help with that. MAybe a moat, and some crocodiles too.

I have had a similar idea for a while, but cost is the problem.

It's private property with no access easily for the public. He did try one container once and it worked ok but still not enough to get below the noise level required. Yes he has one of "those neighbors" Mimms how much noise are we talking? obviously most noise is the breaking of the sound barrier but what sort of noise does this reduce to?

Originally Posted by r87mm

It's private property with no access easily for the public. He did try one container once and it worked ok but still not enough to get below the noise level required. Yes he has one of "those neighbors" Mimms how much noise are we talking? obviously most noise is the breaking of the sound barrier but what sort of noise does this reduce to?

Given where you live, I would suggest you go and have a chat to the guys at Kelly country and find out how they got it done

Ah, if its only to please a shitty neighbor then I wouldnt bother.

Shoot away and be merry.

Sounds like you need something along the lines of a Tank gun/ Howitzer suppressor . Google it and see if it fits?.

I used to be a member of a club that had a 5’ diameter 100m steel tube range.It was a decommissioned flare stack from an oil refinery.The noise inside was ‘interesting...’

Line 30 used car tyres up and shoot down the middle.
It works like a giant suppressor and is free.

To eliminate any heartache, and before you spend any coin, consult your local authority (Council) AND the neighbour. Best of luck with this venture!

Originally Posted by norsk

Line 30 used car tyres up and shoot down the middle.
It works like a giant suppressor and is free.

Buddy and I set this up a while ago on his bush block..........12 used quad bike tyres on a pipe frame extending down range from the front of the shooting bench. Each tyre was filled with Tetron ( soft packing used for protecting flowers for export) and we cut chicken wire into strips to hold it inside the tyres. We then added an electric radiator fan on a swing frame that can be swung across the 'mouth' of the suppressor and ran a lead to the quad bike so you can clear the air between shots. Worked well and even unsuppressed centrefire calibers get cut down to unsuppressed high velocity 22 rounds 100m away. That was until the neighbour built a hut 100m away over the boundary........

Here is a pic.........

Well, there would be a pic if the bloody forum would let me upload it...........

Try again......

Nope......

Originally Posted by Ranger 888

To eliminate any heartache, and before you spend any coin, consult your local authority (Council) AND the neighbour. Best of luck with this venture!

on the other hand, it is sometimes best to say nothing.

All depending on the 'situation'

True 40mm, but it's also good to know what you are up against....

Originally Posted by Ranger 888

True 40mm, but it's also good to know what you are up against....

Also true.

Originally Posted by mimms2

Depends on zoning. If rural then "agricultural impact noise" levels are high and as long as he's not shooting near the cunt's boundary then should be no problem.
There's 10,000 things that affect perceived noise. Cartridge? Powder? Supressor? Velocit, wind direction, air density, reflective/absorbative surfaces and on and on.
As long as the noise at boundary isn't hazardous (<113 dB I think) then neighbour can go spin.
"Most" of the noise is muzzle blast. So supress everything.
Larger diameter pills will displace more air so have "louder" sound signature than smaller ones.

The noise limit that is applicable is the limit in your district or city plan and how & where the plan specifies that the noise is limited.

In my area's district plan the daytime max noise limit is 80 dB.
A 308 target rifle measured a couple of metres behind the mound is 81-85 dB.
At the boundary it will be less.

A council won't generally act or react until there is a complaint.

Once there is a complaint a council has to act. Initially this may be monitoring and measuring to see if there is a breach of their plan. IF there is a breach of the plan's rules then the creator of the noise may be advised to apply for a resource consent &/or an abatement notice may be issued. There are daily fines for breaching abatement notices.

It only takes 1 person, not necessarily a neighbour to complain to trigger the process.
I've seen a passing cyclist start the complaint process.

Talked to owner more and got more info. Council got involved and ended in a court ruling of 55 decibels but not sure where measurements are/ were taken from. Anyway using a modified container with sound proofing materials he got the initial blast noise etc down but the disturbance of the bullet passing through the air to the target produced 65 decibels. As said digging a trench and roofing it will be probably be the best and cheapest option. As luck would have it I may have found about 50m worth of old precast concrete slabs. Will be following up and then maybe make some forms up and make the rest. Thanks for you guys input. Will post the outcome if we give it ago but will be a few months at least.