Brass life

[MagnumManiac]

So guys how about an answer?? How thin is too thin? How do I tell when my grass has had it?

I'm sure I can read the lit on the casemaster but would appreciate your thoughts.

I'll give you a very simple answer.
No matter how many loads have been put through your brass, once you get to the fifth trimming, they are at the end of their usefull life.
As stated elsewhere, the brass is thinning in the critical head/case wall juncture, and a thinning groove may or may not be present.

Think of it like this. If you trim .010" off the neck each time, and you get to the fifth trimming, that's .040" of brass that has migrated into the neck and has been removed.
All brass is not equal in the amount it has at the head/case wall juncture, it varies from each manufacturer. So to be safe this is a 'rule of thumb' put out by brass manufacturers, some brass may go longer than this before it pulls in two, but do you want to run the risk?

 

[Innovative]

MagnumManiac ..........
You're right about trimming the brass. That brass has to come from somewhere. Initially it comes from the weakest part of the case, especially if you have excessive headspace (at the shoulder). However, if your handloads are properly sized to your chamber, the neck trimming is much less, and it has no effect on case life. It's safe to reload most cases 10 to 20 times as long as you examine your cases closely.

- Innovative