10 yards for pistol is the minimum for USPSA matches.
23 feet for pistol is the minimum for USPSA matches, rule 2.1.3.
Steel in USPSA or Steel Challenge will move some when hit, either fall or swing.
Having undamaged steel is important. If it is pockmarked, then ricochets happen. Pockmarks happen when steel is hit with bullets not suitable for targets (e.g., shotgun slugs on pistol steel). Pistol, even major power factor 9 or 38 super from an open gun, will not be a problem. But targets have to be placed knowing where the bullet splatter will fall.