ajridgedell
Well-Known Member
I bought some lapua brass for my .243 thinking it would be a good investment and last a while. After about 4 reloads the case necks are splitting. Am I doing something wrong or is there something else I need to do?
Lapua brass longevity
- Thread starter ajridgedell
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Mikecr
Well-Known Member
It might be excess neck clearance from your chamber.
What do the loaded necks measure?
What do fired necks measure?
What do the loaded necks measure?
What do fired necks measure?
ajridgedell
Well-Known Member
.272 before firing and .276 after. I've heard the term anealing but don't know what that is.
JeffVN
Well-Known Member
0.004 thou sizing is not unusual, especally if its a factory or "tactical" chamber.
go read this an a few more articles on annealing and you'll see that it effectively restores brass to a "as new" condition through a heating process.
Annealing–Restoring Life to your Brass « Daily Bulletin
I anneal my 7WSM brass every other firing, same for my 338LM Improved. My 6x47L gets annealed after 3 firings.
JeffVN
go read this an a few more articles on annealing and you'll see that it effectively restores brass to a "as new" condition through a heating process.
Annealing–Restoring Life to your Brass « Daily Bulletin
I anneal my 7WSM brass every other firing, same for my 338LM Improved. My 6x47L gets annealed after 3 firings.
JeffVN
Mikecr
Well-Known Member
He's not sizing 4thou though.
.276 means chamber is at least ~.277 before springback
And .272 sized minimally to leave 1thou tension after springback means sizing to ~.270
So he's sizing at least 6thou, and the brass is cycling 7thou or more total.
My guess is that he's not minimally sizing the necks though, but FL sizing them(more than needed).
Annealing by 4 firings is fine but should not be expected, or needed IMO.
It is caused by sizing, and NOT by use of Lapua brass.
I can get a dozen great reloads from Lapua in 6br/223 before running into tension variance/need for annealing.
But then I don't cycle brass size so much(or FL size).
Just sayin
.276 means chamber is at least ~.277 before springback
And .272 sized minimally to leave 1thou tension after springback means sizing to ~.270
So he's sizing at least 6thou, and the brass is cycling 7thou or more total.
My guess is that he's not minimally sizing the necks though, but FL sizing them(more than needed).
Annealing by 4 firings is fine but should not be expected, or needed IMO.
It is caused by sizing, and NOT by use of Lapua brass.
I can get a dozen great reloads from Lapua in 6br/223 before running into tension variance/need for annealing.
But then I don't cycle brass size so much(or FL size).
Just sayin
Last edited:
Kevin Thomas
Well-Known Member
ajrigedell,
Our standard is approximately ten (10) reloads, assuming the brass is fired exclusively in one chamber, using normal reloading techniques and staying within safe (SAAMI or CIP) pressure limits. Many will go considerably more than this, and it's possible that some won't make it quite this far, but that's what we normally expect to see from our brass.
There's a host of things that impact brass life, and the guys have already touched on several here already. As they've already mentioned, you need to know a few dimensions to put everything together here; neck O.D. after firing, chamber neck I.D. (do a chamber cast), the neck I.D. of the dies you're using, expander ball O.D., etc.. You get the idea, but what youy're looking for here is anything that's being worked any more than is necessary. Personally, I favor bushing dies for exactly this reason. YOU have absolute control over how much the necks are bing worked, something that isn't true with conventional dies, which generally tend to greatly overwork the brass.
Take a look at some of these issues, and if the problem continues, drop me a line and we'll get it figured out.
Our standard is approximately ten (10) reloads, assuming the brass is fired exclusively in one chamber, using normal reloading techniques and staying within safe (SAAMI or CIP) pressure limits. Many will go considerably more than this, and it's possible that some won't make it quite this far, but that's what we normally expect to see from our brass.
There's a host of things that impact brass life, and the guys have already touched on several here already. As they've already mentioned, you need to know a few dimensions to put everything together here; neck O.D. after firing, chamber neck I.D. (do a chamber cast), the neck I.D. of the dies you're using, expander ball O.D., etc.. You get the idea, but what youy're looking for here is anything that's being worked any more than is necessary. Personally, I favor bushing dies for exactly this reason. YOU have absolute control over how much the necks are bing worked, something that isn't true with conventional dies, which generally tend to greatly overwork the brass.
Take a look at some of these issues, and if the problem continues, drop me a line and we'll get it figured out.
ajridgedell
Well-Known Member
The gun is a 700 vtr, probably no more than 300 rounds fired through it. I'm using about a half grn less powder than the max recommended. I'm using standard rcbs dies I believe it may be sizing the neck more than necessary. Assuming this is part of the problem what sizing die would be recommended? When I get a chance I'll try to measure the neck of a sized case before seating a bullet if that info will help. Thanks for the info.
Kevin Thomas
Well-Known Member
I'd suggest one of the various bushing dies. Redding Type-S, or the Forster, both are excellent. You want a bushing that's about .002" smaller than the finished O.D. of a loaded round with that brass. This should provided decent neck tension without working the brass excessively. Many folks don't even use an expander ball with this sort of set up, and that's an option. I do use one (carbide), but select a bushing that leaves just the faintest hint of when the expander ball passes through the neck. I can feel it, but just barely. That's about what you want. I'll hazard a guess that this should increase the longevity of the brass, and will help turn out more accurate ammo at the same time.
ajridgedell
Well-Known Member
Thanks for the help
Tikkamike
Well-Known Member
I use bushing dies and I am on my 6th reloading in my 338 Lapua with Lapua brass and hot loads and the brass is still like new
