Yikes.. I'm glad I'm at a properly designed indoor range that allows steel core ammo.. Over here, most of the damage is from the pistol calibers.. Slow large projectiles bounce around a lot.. Fast hard projectiles either shatter or dig in without ricocheting. Our backstop is designed so the sparks aren't a fire hazard and it's tough enough to take ANY caliber out there. The reason we don't allow .50BMG (other 50's are ok) is the noise coupled with the fact that it's not a 50yd caliber lol