I built a bunch a AR500 steel targets and have been shooting them a lot. I shoot my .300WSM with 180 Accubonds and 168 VLD's and all they do is take the paint of the steel from 200 yards. The VLD's leave a slight dimple in the steel. One of my friends tested my target out with his .243 shooting a 85 grain Nosler Partition from about 85 yards. The result was A clean hole right through 3/8" AR500 plate. It did not even make a dent in the plate. I was thinking mabe it was a bad piece of plate but I took it to work and tested the hardness on the rockwell tester. It is supposed to be 47 to 52 Rockwell on hardness. You can see in the pic where it was tested. There are a few soft spots on there but they are still really hard.