Hi All
my brass is breaking from the neck
do you think my chamber is to big?
i´m doing something wrong in my reload process?
this brass have at least 5 reloads
i use the rcbs full die

tnks in advance
G.

Chango,

Looks like the neck is being overworked. Chamber should be the first suspect. Do a chamber casting (casting material is available from brownells, called Cerrrosafe). This will give you a casting of your chamber that you can measure and make sure that the neck is within spec.

Kitty

I'm not an experienced enough reloader to give a definitive answer, but could it also be an issue with annealing, or lack thereof, on a particular batch of brass?

I concur with the recommendation to make a cerrosafe cast of the chamber to compare with the loaded OD of the neck. I would also ask the 'smith who chambered it what the neck OD of the chambering reamer is so that you will have a basis of comparison. (It is possible to have a chamber larger than the reamer dimensions if it gets out of control.

All that said, I am suspicious that there may be a problem with the brass. The location and shape of the split suggests to me that the brass may not have been properly annealed. Just because it is Lapua brass does not mean that it is correctly manufactured. They have had problems before. After measuring the chamber cast and your loaded rounds, if things look nominal in that regard, I would contact the merchant from whom you purchased the brass and Lapua USA and ask them to examine the brass.

Simply put, this should not be happening after so few firings if you are using anything remotely resembling normal loads.

If you happened to keep the boxes the brass came in ther should be lot number markings which may be of use to Lapua in tracking the manufacturing processes followed for that particular batch of brass.

Good luck,

Rick

I've had this happen, but never with Lapua ammo, usually happens with Rem or Win brass after such few reloads. One thing that Tubb recommends is that taking the screw out of your resizing die, chucking it up in a drill and running the expander ball over a honing stone, it will take about one thousands off the ball and will eliminate over working the necks on your brass, I've done this to all my rifle and pistol dies, doesn't seem to hurt.

Jim Beckley wrote:I've had this happen, but never with Lapua ammo, usually happens with Rem or Win brass after such few reloads. One thing that Tubb recommends is that taking the screw out of your resizing die, chucking it up in a drill and running the expander ball over a honing stone, it will take about one thousands off the ball and will eliminate over working the necks on your brass, I've done this to all my rifle and pistol dies, doesn't seem to hurt.

Hmm.. I don't even use the expander balls when neck sizing my match brass unless I accidentally drop a piece of brass on the ground or otherwise affect the neck.

I suppose that I should explain that I am a big fan of the interchangeable neck bushing full length sizing dies. Although Redding makes some which are ready to go there is a fellow who will modify any full length sizing die to take a standard size (The Redding bushings are the same size as the original Wilson bushings) bushing for a reasonable price. He does nice work. If anyone is interested, here is his contact information.

Jim Carstensen
[email protected]
563-689-6258 h.p.


You can control the exact amount of neck tension on the case by changing bushings. This avoids not only excessive sizing, but the drag of the expander coming through the neck on the way out which can contribute to case stretching. It also means that you don't have to worry about getting lube in the case neck because there is no need of it. (Did I mention I really don't like case trimming? I've got to find a better system for doing that.)

Rick

The bottom line is you want to work you brass just as little as possible.
Measure your neck on the loaded round. The sized round. and the fired round.
Most people will say the loaded round neck should be .002 to .004 larger than the sized case. And the fired case should be .002 to .004 larger than the loaded round.
Factory chambers will usually run a bit more than this and some custom chambers will run smaller.

Tnks to all for the reply
will try the chamber casting first

Measure a fired case and add .001, that's pretty close to the dimension of your chamber. Measure a loaded round, a good tight chamber is about .003 bigger than your loaded round. There are lot's of things that cause metal fatigue in cartridge case necks, overworking the brass, really high pressure loads, incorrect metalurgy at the factory. Measure the dimension of a sized case with the expander ball removed, measure the dimension of your expander ball. These are all clues that will help you solve your mystry.
Kb