Fortunately I found this thread a few years ago when I started reloading for my Whelens. All three of my reloading manuals show a max of 54 grns of Re15 for 250 grn bullets, but I've been using 57 with 250 Interlocks with no signs of excessive pressure, and have made it a point to shoot in hot weather a few times. Chrono readings range from about 2420-2450 fps.
