XP3 is new this year, so haven't heard a ton about it other than the usual marketing stuff. Concept isgood if it performs like advertised. I am not sure who manufacturers this bullet, I highly doubt it is OLIN (winchester) as they haven't developed bullets for some time. Though they do make it sound like aOLIN design in the info on the press release??

As to the ballistics that is for the 150gr bullet correct? Fine and dandy if your gun shoots it but not all 300 wm like 150 gr projectiles so you'll have to see how your's likes them. Assuming it does shoot well could be a great deer sized bullet. Though for the likes of moose and elk I'd step up to either 180 gr version of it or stick with the AB due to larger mass and possible closer shots leading to less pentetration due to the increased MV or move to 165 Barnes TSX which will give you flatter trajectory but being all copper won't comprimise terminal performance as a result.

BTW 2" at 400 yards is nothing to get hung up over, accuracy and practice rule the roost when dealing with longer range shooting! If you can get both great but don't settle based on a test firing from a gun other than yours and never take the paper ballistics as face value. Only true way is shoot the distances yourself and over a chrony for MV, then run a ballistic program to figure out the variables at those distances.