The current load from the previous owner is 365 grain flat point, 53gr. H4198 for an average velocity of 1798 fps with 17 fps SD.

He supplied 4 test rounds and my first pair at 50 yards (R/L) was 1.5" and the second pair( R/L) was 0.5". I must have flinched on the first

One odd fact is it must use .509 projectiles. Montana Precision Swaging will do that for free so I ordered 100 bullets from him.

He says it shoots 425s well also. He's going to send me all his load data and some more accouterments.

Regarding Brown Bear, some accounts have the Brown Bear as the most cunning and dangerous game; and if I were ever to have that opportunity I'd bank my ass with no less than my .376 Styer.