How do you guys check for thin case head from too many fires?

i have a paper clip, but not sure if I can tell much.

If you really want to know take one of them and saw in half, this will give you an idea. how many loads you run through them so far and do you full length size or neck size.

I load for several dozen calibers. Of course I could saw in half. But my question involves how others feel thier way to see if its about to happen when you get to 5th or 6th reload.

How do you do it?

I really don't want to saw a bunch of cases. I have had one rim be tore off, and another case failure in my several years of reloading.

Its hard to tell what is sizing ring, and what is case head stretch. I have the paperclip trick, but never feel the valley, but I usually toss brass at the 5th load or the brass will lose its ability to hold a primer.

I do neck size alot however. And anneal after the 3rd fire.

I've had one casehead separation in the years I've been reloading, and that was with a .280 Rem. case that I had been loading and using first in my old 725 Rem, as I wanted to see how many deer I could kill with the same case. Ya gotta understand this was years ago when I was a much younger and foolish guy, never giving a thought to the aftermath of a case body stuck in the chamber or the like. Just like death and taxes, it happened. If I remember right, it was on the 9th loading of that case.

Anyhow, I now toss 'em after 5 loadings. I used to try the paper clip trick too, with varying amounts of success. I don't bother looking for stress crack signs anymore, now that I've been taught how to count to five...

Any case head seperation I have experienced was with belted magnums. Just below the sizing ring at the top of the belt. Easy enough to see them starting to go with a magnifying glass. Larry Willis sells a die that will all but eleminate that problem designed for belted mags. I don't shoot my mags all that much, used for hunting only so I never felt the need to buy one. I noticed once I controlled the shoulder bump back to less than .001 I was able to get as many as 8-9 firings. Their not real hot loads either, so that helps too!

I've noticed that on my 300 WM the Remington cases seem to stretch more around the belt than the winchester cases. I see more stretch marks and what appear to be crackling looking marks. I don't know if you've seen this yourself on your cases but I'm thinking they are not as thick at the belt as Winchester's. Just what I've noticed so far. This seems to happen as early as 2nd or 3rd firing. I haven't tried to check the inside of the case I've just been throwing them out.

Just a suggestion. Never tried it before. But I work with Aluminum and we have some device that the quality control guys in the shipping and recieving office use to measure the density ( I think)of the metal we get.It's like a key chain and you just press it on the metal surface and it gives out a reading. Maybe there is some type of gauge made that measures brass in this type of fashion.I don't know but it's an idea that may work better than the paper clip. I don't know what this device is called, but I'll find out Monday.

I think it's called a laser micrometer not sure though.

This post has got me thinking a bit. I neck size with a Lee collet die and am on my 11th sizing. I have had to full length size once because of tight chambering after 7 firings. Does neck sizing reduce the case streching to the point that case head separation is a non issue?

I have been just looking at the primer pockets so far to determine if the cases are OK and they are still tight. I have never had a case separation but I dont reload that much. My loads are pretty hot and after reading these posts I am leaning toward just pitching the brass because I still dont have a handle on how to really know it the cases are weakened.

I guess I am just thinging maybe time to not push my luck after getting 11 reloads.