I'm thinking about starting a twin project for a rifle and XP-100 pistol. I need long-range spot and stalk coyote guns. I'm thinking of a 6mm-RSAUM. The 300 RSAUM case is only about 13% larger than the .284 in case capacity. I'm going to be using bullets from the 87 gr V-Max to the 105 A-Max. I'm wondering though if i'm going too big here. The guns will only be used on coyotes so will not get a lot of use/year. Any comments or ideas on barrel life, etc.??