there is a powder that will work in a .270 and equally well in a .308. I am hunting for a powder for my buddy's .308 that I could try in my .270. I noticed that IMR 4895 was listed in the sierra manual for both calibers. Anybody have any experience with this powder or any that could work well in both? The rifle specs. are: .270 1-10 24" .308 1-12 24"