Russian powder data

I bought 16 lbs of FSP-759 on GunBroker and need data for 300 Wby Mag and 30/06 springfield . The description said load as H380 and the container label says loads similar to Ramshot big game and slightly slower than H380 . The powder was manufactured by Kazan powder plant for Russian military and pulled down for resale at FS Russian Nitrocel Ops#1(Fort Smith Arms & Ammunition Plant). Has anyone here worked up loads using this powder ? Or have any advise ? I've started at 68 grs loading for the 180gr 300 wby mag and increasing 1 gr at a time looking for high pressure signs but the muzzle velocity deviation is crazy big, like 1000 fps... thanks for any info you have to share