I continue to watch it closely and have been very pleased with the durability and consistency. I too have wondered about the rifle cartridges and want to experiment with it but just do not know where to start! I would expect a thicker deeper backstop of rubber crumbs would be well in order and probably do the trick but the deeper they get, the more spread out the backstop becomes. If anyone has some real experience with the crumbs and rifle bullets I would like to know about it so that I would at least have a starting place when warmer weather gets here. I really believe because of cost, EPA concerns and durability that this type of backstop is going to be used more and more. I will tear it down completely this coming summer and have more information to share about the bullets that are recovered.
NRA Endowment Life Member - TX Concealed Handgun Instructor
Experience - What you get when you don't get what you wanted!