I'm new to the .243 WSSm and first loaded one bag of 50 brand new Winchester shells and shot all of them with no problems. I proceeded to load another bag of 50 brand new Winchester shells and so far have fired 41 and all of the empties had cracks in the neck area. I then decided to reload the first 50, now once fired, shells and the bullets (60 Gr. Nosler Ballistic tips) seated with ease on 36 shells but experienced extreme difficulty in seating the other 14 bullets resulting in some damage to said bullets. Has anybody encountered this problem and can possibly suggest a solution? Thanks.

Did you resize the new brass? did you trim the brass to length? what powder and how much?
Did you modify the die?
What gun auto or bolt?

Sounds like that 2nd batch did not get annealed properly @ factory. I'd talk to supplier or Winchester and see if they won't make it right.

quote:

seated with ease on 36 shells but experienced extreme difficulty in seating the other 14 bullets resulting in some damage to said bullets.

Did you chamfer the inside of necks? The WSSM brass is very thick and mouth of cases seem tobe a bit rough on most new cases IME. Trim to lenght and chamfer to insure bullets start properly should resolve that issue.


Regards,
hm

Although the cases were full length sized, I did not chamfer the case mouth, which could have caused the problem.
Thank you all for the advice.