1/2" AR500 is the go to target material for those of you who like to shoot the big boy magnum rifles. This stuff can handle up to .338 Lapua at 100 yards! Thant's incredible! Although I must take this opportunity to say, you should really be shooting your .338 Lapua at distances much further than 100 yards!  It's important to remember that 1/2" AR500 doesn't handle velocity any better than 3/8 can and fast rounds will still cause pitting of your beautiful target. 1/2" shines for magnum calibers because it can handle repeated abuse without warping whereas 3/8" will literally start to wrap around all of your impacts.