Anschutz, you might try 68 grain of IMR 4064 with a good 270 grain bullet. In my old #1 (which I stupidly sold) and also my Mauser (on it's 2nd barrel) , this load shoots extremely well. It kills in line with all the praise I'v ever read about the grand old 375.
The older Hornady Spire Points broke up quite a lot, but their RN did better. Even the spire points did drop elk very well however. With WW Power Points the gun was a death ray on elk and bear.
Used with the new Nosler Partition or Accubond in 260 grain weight you can go up a smidge in the powder charge, but they leave nothing o be desired for killing anything I ever used them on or even saw them used on. Loads around that weight with 4064 seem to shoot well in about any 375 so it's a good starting place for your load work-ups with 260-275 grain bullets.
I also use 4064 for 300 grain bullets, but those I use are all not made anymore except the Partition. Depending on the individual 300 grain bullet bullet I used charges from 66.8 to 68.3 in my Mauser. In my old #1 I used the Hornady RN 300 grain and also the Winchester 300 gr Silver Tips, and 68 grains of 4064 back in the 70s and 80s. Today you can still get the Partitions, the Normas and the Woodleighs and I have read good things about the PPU 300 grain bullets too, but I have never loaded any. >>>>>
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