I just have a Dirt pile, about 7 1/2' high & 15' wide.
I put in 2 - 4x4x8' posts 8' apart, and a 4'x8'x1/2" piece of OSB with a couple of 2x4x8 for support attached to the back and bolted it to the posts.
I set it up for a Pistol range marked at 2,3,4,7,10 and 15 yards.
and 100 and 200 yards for rifles.
I am teaching my Wife to shoot, so it sure beats having to run to a Range some place.
Kevin