Beretz,
That's interesting QL data for IMR4895.
I've used 58 grains of IMR4895 and the Hornady 250-grain Spire Point in three .35 Whelens, one of them a Remington 760, without a hint of high pressures, and muzzle velocities in the 2500 fps range. Of course the Hornady produces somewhat less pressure than the Partition, but still.
Hodgdon's latest data shows 53.5 grains as maximum with IMR4895 and 250's, but I've seen .35 Whelen data take a nose-dive over the past decade or more. Alliant used to list 59 grains of RL-15 as max with a 250 only about 10 years ago, but now lists 54 grains, if I recall correctly.
I don't why this would be so. While there has been a general lowering of maximum loads with the use of piezo-electronic pressure equipment over the past 25-30 years, I don't know of any other cartridge that's seen the drastic reduction of max .35 Whelen loads. Maybe a few old rifles chambered back in the wildcat days had problems, but I've certainly seen to reason for the reduction in any of my rifles with SAAMI-standard chambers.
