Shooting shack design.

[arakboss]

You say you're converting your summer kitchen for this purpose. If it's attached to your main living space in any way, I would recommend against that plan due to potential lead exposure, and if you're preparing meals in the same space as where you test fire, that's a good way to get sick. Won't happen right away, but it will sneak up on you over time. Used to work at an indoor gun range, and my lead levels jumped over a 6 month period, even with using PPE and de-lead soap. Lead poisoning is a real risk, one you should take into consideration when building a shooting space.

It's a separate structure no meal prep will be done there.

 

[arakboss]

How would anything at the muzzle of a firearm stop the sound being created by the bullet breaking the sound barrier as it travels to the target? Unless you had it the full length of the trajectory of of the bullet? if this is your goal I suggest you rent an excavator and dig a trench about 3ft deeper then your bullet will be traveling from the shooting position to the Target.

A suppressor will not stop the sonic boom from a bullet traveling faster then the speed of sound. It will only reduce the sound of the muzzle blast.

Good point. No matter how well the shed contains the muzzle blast the bullet travel may present a noise problem. This is why I should also be focusing on sub sonic loads for shooting at the cabin property.

 

[arakboss]

I am thinking about buying one of these to test sound levels but using an app on my android phone would also be an option. Has anybody compared the two options for testing sound levels.

https://www.amazon.com/RISEPRO-Decibel-Meter-Digital-Sound/dp/B01EZZ8B5Q

 

[arakboss]

I have built a few sound reducing rooms, and a shooting shack or two. My most successful have used curtains of used carpet , carpet on the floor and ceiling.
I hang carpet like you would a clothes line with the bottom just off the ground. and then a second layer just inside that . the second layer should touch the ground but hang down from the ceiling a couple inches. it makes the sound waves travel over one curtain and under the next.
When you get to that front baffle , have several curtains of carpet hanging down.
If that does not give you enough sound reduction extend a couple lines out from the front of the building another15 feet or so.
two or three layers of carpet do a surprising job of cutting noise.
Make friends with a carpet layer to get free insulation.
The shack we did this in is good enough to shoot at night without the neighbors complaining.
The carpet on the walls and ceiling have been there 15 years or so. the floor and outdoor curtains have been replaced a couple times. [ he lives where it snows]. DR

Do you happen to have pictures or a drawing of this carpet hanging?

 

[arakboss]

I need to have a procedure to test out the noise reduction before I spend a bunch of time and use a bunch of building materials for an unknown benefit.

This is my idea for testing the benefits of various improvements or strategies using two people. One will fire a shot while the other one measures the noise level from about 200ft to the southeast of the shooting shack.

Step 1 One person stands near the end of driveway in the road and measures sound decibels of gunshot by person outside and just forward of the shooting shack. That will give a baseline noise level.

Step 2 same test but person with gun fires shot while standing inside the shooting shack in it's current condition (with no improvements made yet). If no improvement in noise reduction was made, reconsider project. If some improvement was made then move on to step 3

Step 3 frame all walls, add windows and door. repeat step 2 test. If additional improvement in noise reduction was made, move on with additional improvements. Continue testing until no further improvements are made. If no improvement is made then call the project done.


What do y'all think, would you test it differently?

 

[nwslopoke]

I looked into the diamond shaped foam panels and they are very expensive. Do you think lining the inside and outside walls with firewood would do much to absorb sound or does it have to be a sealed surface? I have lots and lots of firewood available.

What about those exercise floor mats that link together? Relatively cheap and lining the inside wall might help deaden the noise.

 

[arakboss]

What about those exercise floor mats that link together? Relatively cheap and lining the inside wall might help deaden the noise.

I will look at those if the project gets that far. If I don't see improvement just by stepping inside the way it is currently set up, I might bail on the idea. I text my neighbor down there and she is willing to help with the decibel meter testing. I am going to ask the wife to order the meter tonight. My next trip down there probably won't be until later this month. There is a product called mass load vinyl that is suppose to work very well but it's very spendy. I like the price of used carpet better Used carpet hanging from the walls and ceiling would fit right in with the hillbilly chic theme I got going on down there.

 

[arakboss]

Here is a video from a guy who did some testing on the effectiveness of various materials in soundproofing.




His testing showed that even a single layer of 5/8" type x drywall provided a 64% reduction in noise levels overall.

 

[ilikegunspdx]

I am thinking about building a three sided shooting shack similar in design to the buildings at Tri County but for one or two benches. The main goal would be to minimize the shooting noise from the neighbors. Shelter from the weather will be a secondary benefit. Any economical ideas on how to maximize noise suppression with such a building?

The more it resembles a box with u inside it the more effective it will be. Unfortunately the more uncomfortable and dark that would be though.

If it were me I might look at putting soundboard for Walls on the inside or if not that then maybe layers of carpet padding. There may be other methods for sound deadening on YouTube non gun related videos.

The sonic boom is is a huge, huge factor imo. A simple 22lr that is shooting supersonic rounds that sonic boom travels and travels and bounces and echos. The same gun shooting subsonics you would not hear if you were a ways away from it. The same gun with a suppressor and subsonics wouldn't even be noticeable just a little ways away.

If it were me I would focus on suppressors and subsonic rounds first.

Keep in mind that anything like vegetation etc won't deaden sound at all. My guess on sound reduction effectiveness to the neighbors. I have done a lot of testing on this actually but not nearly comprehensive testing. This includes building a very large earthen berm for the purpose of reducing traffic noise. Also gun testing, but not high powered rifles.

1) suppressor shooting subsonics = 90% noise reduction (generally 30 db reduction and no long distance supersonic sound wave). I have a chart for human perceived noise reduction by db somewhere.
2) sound deadening in shooting shack = 5% noise reduction. Maybe 10% if it's box like but I doubt it would be that high. I have measured with properly calibrated mil-spec meter inside and outside, shooting from big carpeted room though window, with muzzle well inside the room (the room kind of acts like a suppressor so to speak).
3) anything else = 0 %. Two exceptions I can think of to that would be a) wet ground/surroundings, b) nature of the target (think of steel target vs dirt for example)

 

[arakboss]

"2) sound deadening in shooting shack = 5% noise reduction. Maybe 10% if it's box like but I doubt it would be that high. I have measured with properly calibrated mil-spec meter inside and outside, shooting from big carpeted room though window, with muzzle well inside the room (the room kind of acts like a suppressor so to speak)."

That doesn't sound promising.

 

[ilikegunspdx]

"2) sound deadening in shooting shack = 5% noise reduction. Maybe 10% if it's box like but I doubt it would be that high. I have measured with properly calibrated mil-spec meter inside and outside, shooting from big carpeted room though window, with muzzle well inside the room (the room kind of acts like a suppressor so to speak)."

That doesn't sound promising.

It's not, unfortunately. Maher is the best source for info imo on this topic. He has an excellent paper comparing .308 near the shooter and various distances away. It's very thorough. Distance is your friend for sure.

I don't have the links for that paper at hand but this page has a list/links for many of his articles:

Research Interests - Robert Maher, Ph.D. | Montana State University

www.montana.edu

 

[bradsteen]

For maximum sound deadening I would recommend building your insulation in layers. For example, starting at the wall you could do 1 layer of insulation, foam, or underlayment, 1 layer of plywood, 1 additional layer of foam or underlayment, and 1 layer of carpet. That kind of approach should offer a significant reduction in noise signature compared to hanging a single material. Then again, it may also be cost prohibitive.

To keep cost down you could look for used materials on OfferUp or Craigslist that you could repurpose. Scrap plywood, carpet remnants, etc are posted on there with some frequency. If you have a local Buy Nothing forum that would be another option. Rubber exercise mats pop up on occasion, and would make a good insulation material. Do you have a budget for this project you're trying to stay within?

 

[ilikegunspdx]

Found the perceived sound chart I mentioned. Ignore the highlighting as I can't remember what that was for. I figure about 30db reduction for suppressor with subsonics.


The starting value before reduction varies of course, but a lot less than most people think (ie even a short 22 pistol is very loud unsurpressed shooting SuperSonics).

FYI here is a screenshot from another thread showing mrgunsandgear sound testing numbers on 22 pistol with small vs large suppressors. He's a good resource for accurate db levels imo. 22lr is kinda unique though as barrel length has a huge impact and you can get them mouse fart quiet.

Here are some indoor sound numbers in very large carpeted room for 3 barrel lengths of 22lr with small vs large suppressor (Note that the referenced hand clap is the loudest clap I can make which is darn loud as hand claps go, not like clapping at an event or whatever)

With 22 It is possible with suppressor and subsonics to get the shot very close to as quite as just the action cycling. I also recall on mrgunsandgear video where he had a 9mm pcc at 123 db? and action cycling alone was about 116 db l. I have not done 9mm testing in that kind of detail though.

Edit: I'm pretty sure this is the video but did not watch it again to verify.

 

[arakboss]

Found the perceived sound chart I mentioned. Ignore the highlighting as I can't remember what that was for. I figure about 30db reduction for suppressor with subsonics.

View attachment 1235249
The starting value before reduction varies of course, but a lot less than most people think (ie even a short 22 pistol is very loud unsurpressed shooting SuperSonics).
View attachment 1235251
FYI here is a screenshot from another thread showing mrgunsandgear sound testing numbers on 22 pistol with small vs large suppressors. He's a good resource for accurate db levels imo. 22lr is kinda unique though as barrel length has a huge impact and you can get them mouse fart quiet.
View attachment 1235252
Here are some indoor sound numbers in very large carpeted room for 3 barrel lengths of 22lr with small vs large suppressor (Note that the referenced hand clap is the loudest clap I can make which is darn loud as hand claps go, not like clapping at an event or whatever)
View attachment 1235255
With 22 It is possible with suppressor and subsonics to get the shot very close to as quite as just the action cycling. I also recall on mrgunsandgear video where he had a 9mm pcc at 123 db and action cycling alone was about 116 db l. I have not done 9mm testing in that kind of detail though.

What type of meter did you use for the indoor testing and how far away from the meter was the muzzle when firing?

 

[ilikegunspdx]

What type of meter did you use for the indoor testing and how far away from the meter was the muzzle when firing?

You have to have a meter with very fast rise time such as the b and k that mrgunsandgear uses or Larsen Davis lxt or similar. Has to have proper weighting setting, be calibrated, and in peak mode as defined in he mil spec shown below (can't find a way to link the pdf). Distance from muzzle to meter is 1 meter to the side.

Peak of the shot is on the order of 20 millionths of a second or so which is why regular meters won't work.

From a Maher paper:

 

[arakboss]

For maximum sound deadening I would recommend building your insulation in layers. For example, starting at the wall you could do 1 layer of insulation, foam, or underlayment, 1 layer of plywood, 1 additional layer of foam or underlayment, and 1 layer of carpet. That kind of approach should offer a significant reduction in noise signature compared to hanging a single material. Then again, it may also be cost prohibitive.

To keep cost down you could look for used materials on OfferUp or Craigslist that you could repurpose. Scrap plywood, carpet remnants, etc are posted on there with some frequency. If you have a local Buy Nothing forum that would be another option. Rubber exercise mats pop up on occasion, and would make a good insulation material. Do you have a budget for this project you're trying to stay within?

$500 and most of that is going to have to be used on smaller items. I have a bunch of lumber, logs and various other building materials there but I want to get the best bang for the buck in sound reduction. The current structure is about 10ftx16ft. I think I will build a temporary plywood test box to shoot from and collect sound level measurements. Then I can test different materials and techniques in a smaller scale. With four sheets of plywood to start with I could make a 4ft high, 4ft wide by 8ft long test box using earth as floor. I will shoot in prone position for testing. I will build it so I can flip it over and change out wall and ceiling coverings and or add materials to outside of box.

Hopefully the cheap Amazon decibel meter will give me decent relative readings.

 

[ilikegunspdx]

Hopefully the cheap Amazon decibel meter will give me decent relative readings.

It is a 100% certainty that it will not. It will not catch the peak. Must be impulse meter with a very fast rise time. Don't take my word for it call or email Mike at Tornado technologies. Also iraqveteran8888 has a good video on it.

 

[arakboss]

You have to have a meter with very fast rise time such as the b and k that mrgunsandgear uses or Larsen Davis lxt or similar. Has to have proper weighting setting, be calibrated, and in peak mode as defined in he mil spec shown below (can't find a way to link the pdf). Distance from muzzle to meter is 1 meter to the side.
View attachment 1235257
Peak of the shot is on the order of 20 millionths of a second or so which is why regular meters won't work.

From a Maher paper:
View attachment 1235258
View attachment 1235259

I am going to have to make do with a $20 meter. I realize they are too slow to pick up the actual decible peaks but I think they can give me useable relative numbers. If not we will have to use our ears to discern the differences, if any are noticeable. Here is a video where the shooter got some decent relative numbers with a cheap meter. Other youtubers were holding their meters way too close. I will be using the meter 200ft or more away from the shooting position.

 

[ilikegunspdx]

I am going to have to make do with a $20 meter. I realize they are too slow to pick up the actual decible peaks but I think they can give me useable relative numbers. If not we will have to use our ears to discern the differences, if any are noticeable. Here is a video where the shooter got some decent relative numbers with a cheap meter. Other youtubers were holding their meters way too close. I will be using the meter 200ft or more away from the shooting position.

No, not usable numbers unfortunately. Not at all. This is sensitive testing. So much so that I change the orientation of my meter slightly and get different readings. Perhaps watch the iragveteran8888 video to learn more. This is one of those things where you have to have the right tool or you are wasting your time unfortunately. Cheap meters, iPhone apps etc. simply do not have a fast enough rise time to catch the peak. I know I have tried.

 

[arakboss]

It is a 100% certainty that it will not. It will not catch the peak. Must be impulse meter with a very fast rise time. Don't take my word for it call or email Mike at Tornado technologies. Also iraqveteran8888 has a good video on it.

We could also use some other loud sound to test sound reduction improvements.