Does anyone have a rifle chambered in this cartridge or know anyone that might have any reloading data to start with? I may be purchasing one, but would like some info to start with. It is based off the 340 Weatherby case. I believe it is Similar to the .358 STA but want a lot more info before I load anything up. THanks in advance for any help.

Toby

The 358 STA is based on a necked up 8mm Rem case. The 35-340 is based on a 340 case which has slightly more capacity than the 8mm case. So the wby case will likely handle a couple grs more powder (depending on the throat) than the Rem case will. Velocity of the two cartridges will be virtually the same.I would suggest there may be more difference between individual rifles than there would be between load data for these two calibres, they are that close together.