Fill the case with Trail Boss to the level of a cast or jacketed bullet as normally loaded. Dump the powder and weigh it. This is the maximum load for any rifle ctg. 75% of that weight is the starting load.

Beware, it is noted that Trail Boss doesn't like to be compressed. I doubt it is a pressure deal in a bolt gun, most likely an accuracy trait.

For accurate Powder/Puff loads, this stuff is amazing, handgun or rifle, jacketed or cast in rifles or cast in handguns.