300 wsm problem

Was out shooting with a friend of mine and a few of his factory cartridges dropped primers. Factory 180 gr silver tip bullets. Also had problems with them on deer. Made a big splat on the way in and did not exit. Two 100 yard shots did the same thing. Is the bullet going too fast at 100 yards to work properly? Any ideas why the primers fell out? Thanks
H

[Ian M]

Harv,
Not sure if your friend still has the empty brass, if he does then Winchester would like to see them. They need to know the number on the endflap of each box, plus no doubt would like to see the cases.
Had the same thing happen, only the temps were really high at the time we blew a few primers in a .300 WSM.
They have a nice thankyou to maker it worth your while if you go to the bother of sending back stuff like you mentioned. They really need those endflap numbers.