I have hand loaded very little in .458 Lott. Also the largest Woodleigh bullet I have is a 286gr in 9.3mm. I find your question interesting and I think I have a partial answer. I have noticed that Woodleigh RN bullets have a short shank. In the case of the 286gr 9.3 it starts its tapper 9.3mm up from the base to the cannular and then starts its tapper. Thus you have less bering surface and friction and less pressure. I did a little experiment with the Woodleigh and a 286gr Hornady SP by setting my calipers .001" less the bullet diameter and set each bullet nose first to see how much shank is pressing the lands. The Hornady's shank measured 15.75mm or .620". Anyway this is my rational .