Shooting Into Rubber Mulch: A few Questions


May 1, 2013, 08:29 PM
Getting ready to construct an indoor bullet trap, using rubber mulch to trap the bullets. I heard this worked pretty well, but am looking for experiences or comments, and wondering how deep I need to make the impact area to catch .22-.45 bullets. I can refrain from shooting magnums, etc, or add hardened steel to the back plate to flatten any bullets that get through the mulch. Any ideas or comments welcome.

If you enjoyed reading about "Shooting Into Rubber Mulch: A few Questions" here in archive, you'll LOVE our community. Come join today for the full version!
May 1, 2013, 10:28 PM
There are a wealth of commercial sources for "ballistic mulch" out there being used for pistol and rifle bullet stops. You see several products offered in 3ft "super sacks" filled with rummer mulch that make claims of easily stopping high power rifle rounds.

A local range uses rubber mulch in their indoor range and the thickness is variable due to slope.

May 1, 2013, 11:06 PM
At a local indoor range they have this. I've taken a rifle class there and folks were using 308. I've also taken shotgun class there and we were at some point shooting slugs.

May 1, 2013, 11:06 PM
One of our local ranges, Charleston SC's newest range, Quickshot Shooting Range, uses shredded rubber as their backup. Call them, (843) 225-2868, and ask them.

May 2, 2013, 05:04 PM
A trip to Walmart, a cardboard box, and a discounted bag of regular red rubber mulch got an interesting result. I found a medium cardboard box (I was too lazy to construct a larger plywood box just for testing) about 13"x13"x9" and packed it full and tight with the rubber mulch. Then I placed a small piece of plywood at the rear of the box, which was laying flat, presenting a shot though the 13" of rubber. I grabbed my Ruger Security Six with 158gr Magnum JHP's and and put six shots into the box at slightly different places, to avoid a "build up" of lead in any one area. The impacts occasionally pushed the box and knocked over the plywood board resting against the rear, but no shots exited the cardboard box (although one shot apparently caused the box to bulge from the compression of the rubber at the rear; no bullet was at the backside of the box, though.) So, apparently, 13" of well packed rubber mulch just MIGHT be a good beginning for a portable indoor bullet trap. I plan to make a plywood frame, with 18" of mulch packed inside, about four feet square, 20" deep, and a 3/16" hardened steel plate on the back, just for extra insurance against a penetrating projectile. That should take the energy out of any projectile that makes it that far. .................................. ( [
/IMG]- [URL=][IMG] ( (

May 3, 2013, 04:33 PM
I would call Action target and see if they'll tell you what they use for adhesive... when they install a rubber trap/backstop they spray the whole thing down with an adhesive that's also fire retardant IIRC. Helps to hold the mulch in place on a sloped backstop. the backstop also has "steps" or horizontal ledges every so often to prevent all the rubber from sliding down.

May 3, 2013, 08:37 PM
ActionTarget is a great place to start. Also, you can call 3M. I called a while back and spoke to an engineer. They have 2 adhesives which are suitable. One has fire retardant properties. I forget the exact products, but they are very helpful.

May 4, 2013, 08:17 AM
SharpsDressedMan, did those JHPs expand to further assist deacceleration or did they stay unexpanded? My curiosity is to the effectiveness of that same experiement if using a hard cast SWC .357 mag.


May 4, 2013, 09:16 AM
I would suggest a minimum of 24-36 inches deep. I am not a ballistician or expert. My response is based on your given results with 18" test run. The steel plate on the back would be a good idea too. (You might want to angle it to prevent/direct possible richocets.)

Lastly, I advise being extremely careful about what is behind the target area. Be sure that if you miss the target entirely, there is still not going to be any harm to other people or their property.

Better safe than sorry when it comes to firearms. Out of curiosity, where are you planning to build your indoor set-up? Ventilation can be another issue of concern with indoor shooting areas.


P.S. Forgot to ask at what distance will you be shooting? (Measured from the firing line to the FRONT of bullet catcher?) This sounds like a fun project.

May 4, 2013, 02:18 PM
Let's re-evaluate. My first experiment was with about 13-14" of moderately packed, standard rubber mulch as found at Walmart. It stopped 6 full 158gr JHP loads and did not penetrate the 13-14". My plan is to use another minimum of 4" packed more firmly, and back it with a 3/16" AR400 steel plate. I doubt any bullet that manages to penetrate the 18" of rubber would even dent the plate, but would then be flattened, or redirected into more rubber, or both. I have not recovered bullets yet, as I didn't particularly have a reason, but now I will, just to see if they mushroomed. I realize hardcast WOULD penetrate further, but that is not my desire (to find things that WILL defeat my bullet trap). This is a starting point, and it looks as though an effective trap can be built easily from materials costing about $250-$500, depending on if you want a 2'x4' trap, or a 4'x4' trap. Add another $200-$300 for an effective ventilation system and ductwork, and it is starting to look very good.

May 4, 2013, 03:54 PM
Recovered bullets: Four 158gr JHP's and a 90gr.9mm Sierra JHP .................... (

Highland Ranger
May 4, 2013, 06:01 PM
I think I saw a similar design advertised on shooting usa

May 5, 2013, 08:25 AM
Thanks SharpsDressedMan.


May 11, 2013, 03:06 PM
It's a popular backstop material, just make sure to use ruuber that doesn't have the steel from tires in it. That can spark and cause a fire.

If you enjoyed reading about "Shooting Into Rubber Mulch: A few Questions" here in archive, you'll LOVE our community. Come join today for the full version!