Case& barrel life of 300 WSM vs. 7WSM

Daves762

Well-Known Member
Joined
May 7, 2011
Messages
382
Location
In a Free State
I'm trying to order my first custom barrel or fancy barrel or expensive barrel or whatever you wanna call it.

I'm torn between 300WSM and 7mm WSM and I think that case life could contribute to my decision.

I have also read in several places that the "overbore" calibers like the 7WSM have short barrel life AND case life.

#1-How many rounds can I get our of each caliber before accuracy drops offdue to throught errosion?

#2-How many reloads of brass can I get out of each caliber before necks split?

I know the 270 WSM is terrable on the case necks and some of mine have split after just a couple loads WITH anealing...I want to stay away from that.


Thanks.
Dave
 
Last edited:
Brass should last forever. Whatever you're doing to cause neck splitting needs to be figured out & corrected.
Otherwise, YOUR brass life is an abstract.
 
Sorry, I don't know why your 270WSM splits necks.
Hopefully someone here who does will chime in.
I could picture this only with disposable loaded factory brass(like the stuff bought at Walmart), instead of actual reloading brass.
 
Daves 762,
I'll try to hit the high points in some sort of order that MAY make sense.
First, there really are very few cartridges that are "overbore" any more. With the selection of powders today, read incredibly slow, it just isn't so. We may run out of barrel, but there are usually suitable powers.
As far as barrel life, that will depend entirely on your shooting and cleaning habits. Rapid firing (heating things up), pushing the envelope, and too little, too frequent, or improper cleaning will also shorten barrel life. There is some good evidence that some of the new bore treatments can make a difference in cleaning and barrel life. Do a search... Microlon and Ultra Coat for example. Between your choices, I'd have to give the nod to the longest barrel life to the .30 caliber over the 7mm. A rough guess would be somewhere about 50-100 rounds. IOW, it won't matter enough to be significant, all other factors equal (and they never are).
To address your brass life, in short, there is something wrong. There is no GOOD reason a prudent loader shouldn't get close to 10 firings from a quality brass case. Pushing pressures and overworking cases are the biggest culprits. Use a chronograph, and keep speeds where they should be, to control pressures. Speed equals pressure. Again, that is a generalization, but it applies.
Finally, to address your neck splitting problem. You need to measure... The diameter of: new brass, loaded brass, fired brass, sized brass (without expander), and sized brass with expander. I'm gonna bet your widest spread - between fired brass and sized but not expanded brass - is gonna be pretty large. That is where you are overworking your case necks. Keeping this spread to a minimum will increase brass life. CORRECT annealing also helps, but too little or too much (cooks necks) isn't gonna get it. If you can keep your neck movement within about 4-6 thousandths, and correctly anneal, you should have no more trouble with necks splitting.
Hope this helps................Bug
 
Huge difference in barrel life.

Most of the 7 WSMs are under 1000, sometimes well under.

Most of the 300 WSMs are way over 1000. My first comp barrel had 2400 rds and I took 5th in the Nationals with it. Danny Brooks won the Nationals with a 300 WSM in 2009 for LG group and Scor, HG group and 2 Gun overall and his LG had over 4000 rds down the tube.

As for brass, a good set of properly fitting FL dies and annealling will make your brass last over 40 firings at least and not powder puff loads either. Most guys NS because their dies do not fit correctly and they do not know how to adjust them.

BH
 
Well I suspect my sizer ball is wrong.

But Ive had the brass split at first firing too.

My loads aren't near max pressures and I'm a moderatly experienced reloader and never have encountered this with any other rifles.
 
I have a 300 WSM that has had the same sort of problems. Out of 2 bags of 50, I had one case in each bag that would not even fit in the shell holder (problem with the rebated rim dimensions), and I lost 2 cases to neck splits on the very first firing which leads me to believe that there was a problem with my particular lot of brass. However I'm on my 3rd load on some of the cases now and I've had zero problems since.
 
Well I need to buy different brass maybe. But Lapua doenst make 270 wsm to my knowledge Im using Winchester brass and might swich if this persists.
 
Yes its Winchester reloading brass.

I have the head spacing tight enough to be slight resistance on closing the bolt as my chamer is oversized according to my case head space gauge.

I anneal them every 3 firings now and it appears to have decreased significantly, but still exists more often than any other catridge I load. It is however my only "magnum" cartridge so I know there is a learning curve.

Thats what I'm trying to do here, learn.

Thanks to all that have pointed my in the right direction.
 
I also have a 270wsm and bought norma brass, have not had any trouble with spilt case necks and I know I am at pretty high pressure I have shot each brass 5 times with no issues ,I bought some winchester brass for my sons 7wsm and was inspecting brass before neck turning and had 15 brass out of 50 that the necks already had a small split so I set it aside got some norma brass in 300wsm sized it down, and fire formed it, have not had any trouble with this brass either, winchester brass is hard but I have had experiences that made me wonder why its not always up to par.
 
Warning! This thread is more than 14 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top