Why would i have neck splits on twice fired brass? I loaded up some twice fired brass for the 30/06 the first time fired was factory 180 grain remington the second time i loaded up under max with 180 grain and now i loaded the same 180 grain bullets under max. Out of 120 rounds fired i had 6 cases with neck splits all about 1/8". I usualy throw my brass out at four times fired and never had neck splits before .

Yeah, that seems a little quick. I've got some Federal '06 brass that is reaching end of life after seven or eight trips through the same rifle - a couple neck splits per 50 - so they have been moved to the reduced load category. Is the brass all from the same batch? Is it nickel plated? Have you changed your resizing lube? Is it all being fired in the same rifle?

Unless the neck in your chamber is slightly oversize, I would think you jus got a bad lot of brass. I had this happen once w/ 30-06 brass from WW.

Yes its all from the same batch of 100 i purchased a while ago its remington brass and was used in three different rifles but i didnt notice the cracks untill the end of day so i cant say if they all cracked in one particular rifle. I think it must have been a bad batch but i'll keep a sharper eye in the future.

Tanoose, something's rotten here (with your brass or your chamber, that is). Brass should last through five trimmings. My -06 brass frequently lasts more than 20 loadings. If you want to get to the bottom of it, let's go through it logically.
1. What are you firing them out of?
2. Are you resizing full length? Small base? Neck?
3. Have you had a problem like this with the rifle before?
It could be a bad batch of brass i.e. not properly anealed. Something has made the brass too brittle, and normally that happens from overworking it, but usually doesn't begin to show until after many firings. However, if the chamber is too large and is allowing the case to obturate fully, resising it can cause the problem described much sooner.
4. Measure the inside and outside neck diameter and the shoulder diameter of a fired, unsized case and compare it with your sized cases. This will tell you if your chamber is the culprit. Military rifles sometimes have oversized chambers to facilitate feeding under adverse conditions, but production rifles can have problems, too.
If the chamber is within specs., the most likely scenario, then it's the brass, and I would simply anneal the case necks or buy some new cases.
If the chamber is oversized, depending on how much larger than normal it is, your options are to live with the short case life (not very cost effective), modify your sizing and seating technique (treat it like a wildcat or IMP case and work the brass as little as possible like you often must with a .303Brit), or rebarrel the action (expensive, but sure to cure the problem).

also if you are full length resizing after each firing you are over working the brass which makes it hard 3 times would be about right.

With three different rifles, it's going to be pretty hard to diagnose your problem. Two loadings is unacceptable. I would say that the way for you to get decent case life is to segregate the brass for each rifle, measure them all to figure out if one of their chambers is the culprit, and to neck size the cases in the future. FL or SB sizing is going to shorten your case life by quite a bit, but you can still get a lot more use out of it by anealing them.

I've got cases fired upwards of 10times from rifles, never got a neck split. The one exception was a batch of WW brass, about every 3rd firing I'ld get a split neck. Primer pockest were tight too. The firing from three diff. rifles may be a part of the problem. I'll bet they all have diff. dimensions.

Mike a case after resizing and then mike it after firing. That might show a problem with you chamber.

But it could be a batch of brittle brass.

No, I don't anneal.

pull out the expander nipple on your dies & size a case to see if the die is overdoing the neck. I once had a set of 264 dies that if I pulled the nipple I could almost seat a 6 mm bullet in the case. Those necks went to hell in a hurry too.

Thanks for all your help i to have never had this problem so soon. I started using small base dies for the 30/06 two years ago when i bought a ruger77 ( i had this same problem with a ruger 77 in 338 )the standard dies didn't size enough to chamber back into the ruger but i never had that problem with the remington 700 and 760 which were the other two rifles used and all brass was run through the small base dies.I think i'll use the standard dies for the remingtons and just use the small base for the ruger or maybe i can adjust the standard to the ruger. Anyway i'll start off with some new brass and mark them for each rifle. Thanks again Tanoose

Most likely it's the brass.

I've reloaded and fired the same 06 and 223 cases over 60 times each full length sizing everytime and seldom crack a case.

I don't load to the max ever, have never annealed a case either an been loading since 1958.

Thing about 06 and 223's is they are throw aways for so many guys you'll never have a problem getting more IF you inhabit a popular range, or shooting area.

George