Much could have to do with the quality of brass.. Hagel found WW brass much better for making .340 WM brass than the stuff Norma was producing.. That is what I used for my .340 No problems yet.. I have loaded for Mag.cases all my life, and have had a few cases separate but a crack was easy to spot when loading.. After a few of those, I would discard that lot...
Good advice and im sure when you reference WW brass, you are talking about 60's, 70'and maybe 80's brass. The chidt they make now days is garbage. R-P was way better than WW in the 90's and early 2000's, as well.
