View single post by Don Fischer
 Posted: Sun Feb 28th, 2010 01:48 PM
 PM  Quote  Reply  Full Topic 
Don Fischer

Joined: Thu Aug 27th, 2009
Location: Antelope, Ore
Posts: 680

  back to top

Case head seperation is caused by excessive headspace. But in the case of belted and rimmed cartridges, it ain't necessarily so. With those type cartridges the cartridge headspaces somewhere other than the shoulder of the case. As a result, often usually the headspace is correct but the chambers are sloppy. Then you fire a case and it expands out to fill the chamber. Then in FL sizing you move everything back where it was and the process starts again. Each time the brass is pulled from the head to fill the case and the more times that happens, the thinner the case gets there and seperation starts to show. Because of that, I used to particial re-size belted and rimless cases. Particial resizing not only fixes the problem there but can also be used to remedy excessive headspace in a rimless case. I don't particial resize rimless cases though as I don't feel the gain is worth the effort of setting up a die for it. Rather I will neck size several times then FL when the case get's hard to chamber. I've never had to worry about headspace in a rimless cartridge.

EDIT: I should add that primer pockets shooting loose is a product of pressure. I have them shoot loose myself and it caused by my loads being a bit hotter than they should be. If you are shooting a load that is always well below max, the pocket's will last much longer. I don't anneal either as I find I usually shot primer pocket's loose befor a need to anneal. Again that is caused by hotter pressure and is one reason I don't post's loads on the internet.

Last edited on Sun Feb 28th, 2010 01:52 PM by Don Fischer

I pity the man that has never been loved by a dog!
 Close Window