The bullets are a 405gr .460 diameter hard cast of unknown alloy with a semi wadcutter profile. I've slugged the barrel and found .464 grooves and .454 lands. I know that there are better bullets but these came with the rifle and there are nearly 400 of them so from an economic standpoint I'll be using these for a while. It also came with some 350gr but I don't think I'll be using those as I have read accuracy falls off as the weight goes down. I didn't load these rounds so I can't vouch for their consistency. I weighed them and only used the middle average ones but none were the exact same weight. I believe they were charged with a Lee dipper and not a scale as that was part of the die set that came with it.
Once I get the small issues with the rifle completed I'll concentrate on the loads. Even with an undersized bullet I should be able to tighten the grouping some. I'll start hinting now about the bullets I want for my birthday.