In a firing range
, a backstop is anything which is used to make sure bullets fired
downrange do not ricochet
back to the shooters or fly farther than the shooting range.
For most pistol and rifle rounds, a huge and tall pile of dirt in front of a concrete wall is sufficient, sand bags are also very effective but will get messed up and tattered as they get hit.
Some smaller firing ranges, especially the indoor ones, use a flat steel plate that is installed at an angle. The bullets hit this plate and ricochet downwards to a bed of sawdust or sand. It makes quite a noise, the lead hitting steel not the sawdust.
Though I have not heard of any untoward incidents with this steel plate backstop, I feel uneasy shooting at a flat hard surface as this is also a no no in gun safety.
Piles of dirt or sandbags make safer backstops.
to all :-)