300wsm cracked cases

[Tron28]

Back in Feb. I got a new x-bolt in 300wsm. I've been working up loads for it with 180gr Hornady Interlock's spbt. Speer spbt in 165gr and now the Barnes TSX in 165gr. All of it was over H414 using Winchester brass and cci magnum primers.

I did not like what the 180gr loads were like so I switched to the 165gr bullets. The Speer's i got to 3/4 of an inch but the Tsx's are better.
The load i settle on is 165gr Tsx, 65.5gr H414, CCI magnum primer and Winchester brass. .050 off of the lands. 3030fps. 3 shot group at a 100yrds is a ragged hole.

Im not sure how many times this brass has been loaded but im sure its not more that 5 times.
They are cracking horizontally around the case neck and shoulder. I did notice that the brass was very soft and easy to trim. I suspect that it just can't handle being worked and is cracking do to that. (work hardening). It reminds me of toffee. Nice and soft and will bend, but you hit and it cracks.
My old 30-06 brass was 1 fired factory ammo that i loaded more than 10 times and never saw any thing like this.
I realise the metal has been work hardened but am just wondering if this is more normal for this caliber or maybe this is a bad batch of brass. Also with a small pic you can feel the cracks on the inside as well.
There are no pressure signs on any of the brass or primers.
Here are some pic's.

Thanks
Tron

 

[sbtennex]

Looks like simple fatigue from work-hardening. Depends on how generous the chamber is in the rifle they're shot in - if the neck is being squeezed down say 10 thou every time, they're gonna crack eventually plus that you don't know how many firings they've endured. Add to that the higher than average pressures the caliber with those loads runs at and it's inevitable. I'd start over with new brass and keep track of the number of firings. Annealing should help prolong the neck life if they're taken to the right temp every 3rd or 4th firing. Brass is cheap enough to not take chances. Separate one in the chamber and you'll see what I mean.
I'd also be taking the resizing die(s) apart and cleaning them really well - those longitudinal scrapes don't look healthy.

 

[Suka]

brass

I'd suggest taking a look at the very end of the neck (it's thinned out) that it's just reached it's service life.
My wife's 3030 brass looks like the end of the neck after 7, my dad's 270 is only good for 4 or 5. On the 270 the neck stretches.
Maybe keep 5 or 6 new brass loads seperate, and make sure of how many times they're reloaded. I'd wager you'll find it's consistant, as long as your loads are.
Both the wife's and dad's are very consistant in those numbers.

 

[Tron28]

Thanks for the input. Ill just have top keep track of them better.