I shoot as a civvy on MOD ranges and there has been a spate of this sort of thing. I am given to understand that the hard targets at Sennybridge (Scrap Ferrets) can no longer be shot at because of "the danger of ricochets". What the hell the range warden thinks they were put there for remains a mystery.
No problems in all the years the hard targets have been on the range but suddenly some "risk averse" numpty takes over the job and everything grinds to a halt.
FFS, I could write a safety procedure for a grenade range in an afternoon - it's not as though you need some special facility.