Brass cases getting shorter?

[GlockTerrier]

Hi, guys - as I've admitted earlier, I'm a relative newbie in a handloading - and here's what I want to ask from my respected and experienced colleagues in this new to me craft:

I'm reloading .223Rem. Originally I had my once fired cases trimmed to 1.753", necks chamfered and deburred, etc. What I'm noticing that by 4-5th reload most of my brass got shorter well up to 0.010" to 1.743" with original chamfer still seemingly intact - and I don't have to trim anyway...

What's going on here? The neck's were chamfered too thin and their tops were blown away? Brass hardened and doesn't stretch anymore? Should I ditch it already or is it safe to continue reloading and wait until they stretch again? (I don't see much of any other bad signs (splitted necks, bright lines, too loose pockets etc. - and I don't load them hot..)

Thanks in advance for any insights and comments!

 

[scrat]

Ditch the brass for sure.

On rifle cases. Some people like to do full sizing. I prefer neck sizing only for the most part. Brass will only stretch out so far. By neck sizing only you will get a lot more life out of your brass. When you full size them all the time you are strectching out the brass too much.
One thing to check after a few full sizing. Take a paperclip. Bend it all straight. then bend the end to look like a little L shape. Then put the Hook part all the way in the case towards the back. Then touch the sidewall and slowly pull towards the front feeling the wall. If you feel a step or if you have a crack internally you will feel it. IF your brass is good you should feel nothing from the back to the front. For sure though id say you got the life out of those cases. I would for sure get a collet die. (neck sizing die). This will prolong the life of your brass a lot.

 

[gandog56]

Neck sizing is fine for a bolt action rifle in .223. But it is not recommended for semi auto rifles.

 

[scrat]

Thats right i totally forgot about that. You would have to full size for semi auto. LEver action and bolt do not require full sizing.

 

[SilentArmy]

Dry your chamber after cleaning. Any oil left in there can cause ths case not to grab the walls of the chamber when fired and you can get the case shrinkage. I have noticed this in the .50 Beowulf. Kinda suprising to see your brass get shorter huh?

 

[Walkalong]

Brass "shortens" when fired and is squeezed/stretched back to full length when sized again. Did you measure after it was fired or after you sized it again?