I love the death out of the round but the one i have right now will about only shoot 180 grain tsx barnes. It shoots 5 shot 100 yard groups 3/4 of an inch with them and re25 and the group isnt much larger at 200. but about any other bullet does 1.5 or more. Its just a cheap wby vanguard but ive changed the trigger, even bought a laminated stock and bedded it and firelapped the barrel but nothing changed. Im not a big fan of barnes bullets but i guess in the 300wby they will kill! Just last night I shot a doe at 465 yards with it. Dropped in her tracks but then i have to admit i hit her right in the spine. Ive had two bdl stainless 300 wby remingtons that werent near as finiky but lost all my loading data for them in a fire.
I'm using H1000 powder with a 180 accubond and a fed 215 primer . another powder to give a try would be IMR7828 . I played with it a little and it was showing good promise with the same bullet and primer . Jim