I have a custom chamber, Hart barrel, in a 340 WBY caliber. I want to load Hammer Shock, 225 gn. bullets that can be loaded to a .020" jump. The traditional Wby freebore is gone so I can no longer use the loads from the loading manuals as a guide. I am all about being safe and I am not confident in knowing where the starting loads should begin. I would like to begin with IMR 7828. Maybe I should use the loads for the 338 Win Mag as a starting point. Don't want to be too light but certainly not tooooo much. Any guidance will be appreciated. THANKS