split necks in 300wsm

Status
Not open for further replies.

jk.308

Member
Joined
Jan 1, 2012
Messages
20
Location
charleston, wv
I normally just lurk and read what everyone else posts and say but I am having a particular issue that I can't seem to figure out.

I have a browning abolt in 300wsm that I have been trying to work loads up with. I found a load that shoots 3/4in, which would be great but I seem to split 1-2 necks per firing. Now I would guess this to be a pressure issue but this happened from starting powder charges up to where I am at now. The load i found to shoot well is 63grns of IMR 4350 with a 180gr nosler bt. I checked my dies to make sure they where set properly and then went ahead and annealed the cases. They still are splitting. Just wondering if anyone else has any suggestions to try short of taking it to a smith as it is only 2 months from rifle season.

thanks
 
Are you sure you annealed them properly? I can't think of anything that would be wrong with the rifle that would just split the necks.
 
In all honesty i can not say for sure that i did, as this is the first rifle i have ever even seen a need. I annealed them to a blue tinge on the case, before letting it turn the least bit orange......other than that i would guess there could be the possibility it was done incorrectly.
 
That should have annealed it enough. It's possible the neck area of your chamber is oversized. Measure the neck diameter of a fired case and compare it to a sized one.
 
fire measure .332 and a never fired new case was .326......just to see i went and measure a sized and fired 243 case. it measure .260 sized and .265 fired so it seems close.
 
Are you sure you annealed them properly?
I guess I am stupid. Why would you anneal the cases? I have never annealed any round and I reload for dozens. Someone enlighten my ignorant self about the need to anneal. BTW, I have had that problem with cases that were stretched from lots of resizing and needed to be trimmed to spec length.
 
I'm not saying that there is no need to aneal if case life is short lived with a particular cartridge. Other wise, you may be unnecessarly adding one more step and issue to deal with, to an other wise simple process. I don't anneal and I rarely ever experience a neck failure, it's usually an incipient head seperation that will expire my brass. I don't load for the 300 WSM, so I don't know if it is especially hard on necks, but case life for most of my chamberings is no less that 7 or 8 runs, and I get up to 12 loads from some if I keep charges around mid book.

How many times has the brass been reloaded? If it is splitting right from the get go, it's likely something your doing, or the chamber needs to be looked at, in my opinion.

GS
 
I'm from the old school. I thought the way you annealed a brass case was to stand it in a pan of water deep enough to cover the case when lying down. the water served two purposes, one to protect the thicker base and two to anneal the brass. Brass, opposite of steel, softens when quenched in water. Brass left to air cool will harden. Heat the brass tio red and tip over into the water to quench and thus anneal the thin neck.
Please correct me if I'm wrong, but this is the way I learned too many years ago.
 
You don't need to quench brass when annealing. Heat it and let it cool. The only part water ever plays is to keep the case head cool.
 
The quickest I have gotten one to split was on 2-3 loading....I would agree it is something I am doing but my dies are setup very close to my 270wsm which has had no issues with the necks......they normally get retired due to loose primer pockets......I clean my brass every time so I wouldn't think my die would be dirty.....only thing that leaves me with is a chamber issue I suppose.....
 
i've had brand new winchester brass get split necks on the very first firing. i've read a lot of posts where others have reported the same problem.
 
That is interesting as that is what I'm experiencing this with.....I found a bag at cabelas and thought I hit the jackpot....looks maybe I didn't if others have had similar issues
 
i picked up about 25 or 30 pieces of nickel plated 300 WSM brass yesterday at the range. i'd sell or trade it if you're interested.
 
jk 308, the ‘S’ as in short when it comes to magnums means the case gets a work out when fired, the ‘SS’ means super short, same thing only the case takes a beating. A common complain when sizing cases for S and or SS cases sounds like this “After firing my short magnum cases or super short magnum cases they will not chamber without felt resistance to bolt closing”, the short fat powder column has a an adverse effect on the brass.

The usual advise when correcting the problem never gets around to understanding the problem, change lube, another press, more expensive dies etc.. Short and Super Short Magnum cases take a hammering, applying the rules of cases with long/small diameter powder columns does not apply.

F. Guffey
 
It has nothing to do with the powder column. The brass is more prone to cracking because it's a more drastic change from body diameter to neck.
 
Try Norma 300 WSM brass. I'm on the 8th loading of mine. It was just on the last loading that I realized I should anneal them before loading next time. If I do, feeling it out I probably have a couple more loadings before the primer pockets get too loose.
 
It's possible that if the cases weren't properly annealed during the forming process that they were already cracked before you fired them.
 
I think what fguffey said makes sense. A large volume of 70K + psi gases being forced off a sharp angled shoulder, I can certainly see the potential for neck splits, especially where the neck meets the shoulder. I would bet that even with annealing, the WSM might be prone eat brass for breakfast, lunch, and dinner.

GS
 
thanks for all the suggestions....rat i appreciate the offer but i think i am going to try the annealing thing again, then do it every load or every other load to see if it will prolong the life of my cases.....

about the norma brass, for what i could read it is a very stiff brass which i feel may be prone to neck splits as well. It just confuses the crap out of me that my 270wsm cases are on 8-9 loadings i believe and have not got one neck split....
 
Status
Not open for further replies.
Back
Top