I had a chance to test out my steel targets today sort of. Used some scrap steel from a project at work. Shot this one at 657 yards with my .300 RUM and a 200 grain Accubond. The plate is 1/2 inch thick. Only test I did as I used my biggest gun for the research. Might work for my .22's and 6mm's. Possibly the .270 and .06. Gonna do more shooting, today I was in a hurry. What kind of steel do you guys use? I have heard AR500 is the way to go. mtmuley