Targets must be constructed of paper, cardboard, ballistics polymer, or similar material that will not shatter or cause bullet ricochet. Metal targets may be used for special events if approved by DNR in advance.
Well a park ranger down in LaGrange told us we couldn't shoot a pumpkin with a buddy of mine's new FAL because it would cause ricochets. Don't think they allow steel targets down there anyway, though with the general IQ of the majority of shooters down there I feel it isn't a huge loss, the guy setting up the .22 spinner target at 10 feet was a clue that there might be wisdom in disallowing steel targets.