Welcome to the Nation Butch! Those of us who own the 6.5-300 bee, have them in the Mark V. I personally own an Accumark, and what has been the factory ammo that most of these rifles like is the 127 LRX. However, your rifle will be the deciding factor on which ammo shoots better. In regards to the lightest Vanguard rifle made, it is the Vanguard Synthetic. Let us know what you end up buying.