Welcome Mike.. I fixed your gargantuan pics so theyre a littel easier to view.
I bettn money you got ahold of some bad brass. and thats why it split.
I also just cross referenced the data youre using too. I feel it may be a tad undercharged. Hornady doesnt list IMR 4350 for use under its 87 gr V max, and none of my other manuals list the 87 gr V max, but looking at data for a 90 gr bullet and IMR 4350 the starting charge for a slightly heavier bullet is in the 42 gr range. IMR 4350 is one of those you cannot undercharge with because you can easily get secondary explosion due to too much empty space in the case. Which could also be aiding your split necks, though i think youd have had problems with stocky bolt lift and extraction as well.
I also notice you mention the 87 gr Vmax for deer hunting. I gotta advise against that one too. The Vmaxes are too lightly constructed and will explode upon impact and increase the chance of wounded game. Meaning your wifes doe will likely hobble off into the woods with a gaping flesh wound and a broken shoulder.
I do have a very good shooting load I developed for my wife using 85 gr sierra gamekings and Alliant 4000MR and I dont mind sharing it at all.
CCI250 primer
44.4 gr 4000MR
85 gr SGK
Good for 3150 fps in a 26" barrel and is half MOA.
SO I guess my advice is for you to get a different batch of brass. Choose a different bullet and make sure you arent undercharging with IMR4350.
