22 Cheetah brass issue

I have a friend that has had a 22 Cheetah for years, forms and loads his own ammo
He showed me some brass that he had sized and loaded about 1 year ago but did not fire form them at the time of loading
Decided to shoot for the fireform and the shoulder split on the cases
He told me this was the first brass he has had split with the only difference being the rounds set for a year before firing.
We decided to remove the bullets and powder/primers on the remaining shells and anneal the cases
After annealing 20 out of 30 cases split at the neck when sizing in the press
Brass was rem br 308
the only thing he has done different from all the previous rounds he has made was letting the brass set the year before fire forming


Anyone have any idea what is going on with the brass?
Thanks for any input- this has me stumped
Jack

Its just a bad lot, it happens, conatact Remington.

Also could be annealing temperature. Most common problem w/ annealing is not getting neck hot enough (750 to 800 degrees). Liquid Tempilac is an excellent indicator of temperature. Check out the info @ ballistic edge mfg. regarding use of Tempilac which will take the "guess work" out of the annealing equation. Proper annealing wouldn't leave you w/ split cases after only one year. Just my thoughts.

thanks for the replies
Talked with my friend today about what you guys think
He is going to try and anneal a few more rounds
What is strange about this is that this was new 308 rem brass, all the same lot. He has loaded quite a few rounds previously with no issues
It was necked down in 3 or four stages and loaded to fireform
He is confident that if he had fireformed them at that time, instead of waiting the year, they would have been fine ( which is how he normally does the loads).



I was wondering if anyone had run into this type of problem
He is going to order some new brass but we would still like try and figure out what happened
Again,
thanks for your input
Jack