This topic is of interest to me, because I'm working up some loads in my .338 RUM, and the velocity I'd expect just isn't there with WC872. I've put 103 grains of WC872 behind a 225 grain Hornady bullet, lit it off with a CCI 250 primer and I only get 2651 fps! This is in a Remington 26" factory barrel with a vais brake. The 103 grains is getting close to a compressed load. I have to shake it down pretty good to get it to the bottom of the neck.
Using 95 grains of WC852(s) with the same setup I get 3165 fps. No pressure signs with either load. What gives? Any ideas?
Mark in Utah