I have a six-plate vertical steel target with several different plate sets for different pistols . Most sets are 6 inches tall and 7 inches long welded to tubes that the rebar slides through . I don't have any way handy to measure the angle , but it's quite a bit . We have a set of 1/8 inch non AR plates for .22 LR and it is now very " wavy " from thousands of flip-flops . Our steel shop does not stock 1/8 AR , so we had a set of 3/16 AR made in 5 x 6 inch size . Half again as thick but 42 sq inches vs 30 sq inches , so about the same weight . These work fine with Colt Aces and CCI mini mags at 15 yards . Bounce back is no more than 5 yards with any handgun / plate from .22 to .45 ACP and 10MM ( 45 set is 1/2 AR ) , but we don't go any less than 15 yards . You must go thick enough to not get any craters , those can introduce variances that can send bounce backs anywhere . I also made two horizontal 6-plates rack with the plates set at the same steep angle forward for shooting down and backwards for shooting while hanging down . No bounce back past 5 yards or so .
Chris