I"ve been running 230 RN over 3.7 Clays with an OAL of 1.26" -- clocks @ 755 fps, surprisingly easy on the recoil for a major load, but a touch on the smoky side (no problem, just occasionally noticeable, depending on the wind/heat/humidity combination).
Leading has never really been a problem.
Same here. 230gr S&S Cast Bullets, 3.7 Clays, OAL 1.25. 755 fps. No problems with leading.