[gman51]

Sorry did not mean to hyjack your post. Thought your trap was really really good and simple to make. I might just use your idea to do some more traps. Notice my use of freezer paper and paint as target. Don't even have to buy store targets.
It is great to walk out the back door and shoot isn't it. Much cheaper than range and no gas to get there.

I have 2 acres and can shoot here in the country. Pic is of my bullet trap as first made. It has two layers of landscape timbers covered with plywood. The bottom layer of timbers were deteriorating pretty bad and had a few rounds get through. To make it better I enclosed sides and put layer of 4x6 white oak on back of front section. Then I filled that boxed area with sand. So sand is about foot or so deep. Now bullets stay in trap. I periodically remove the bullets from the sand then just repile the sand back up. I bought 1/2 yard sand from local dirt center and used maybe 1/2 of that.
I use rolls of freezer paper on the top curtain rod and pull down and clothes pin to bungie cord at bottom. I then spray paint a bulls eye on the paper. As needed I just pull more paper down and paint another eye.
All really need is build a 8 ft tall box maybe 4x4 and use 2x6 for flooring to support sand as in pic. Also using rubber truck mud flap on sides and front behind the target will help keep sand in place. I had checked using sand on utube and 9mm or .45 would barely get to back side of 6 inches of sand. Google and check it out.
I also built a back stop 4X6 white oak with hanging wood blocks on pvc in front for shooting .22. I do not use this for anything over a .22 as larger caliber bullets will go through the oak back stop.