I've been loadin for my bro-in-law's 300rum using rem brass, retumbo, and 200gr ABs. Today he showed up with some once fired federal brass and asked me to load them for his hunting trip. Has anyone loaded with this brass? Am I gonna need to change the powder charge at all? Any imput would be great cuz I'm not about to give up any of my brass since it's nearly impossibe to find now.