Extending Cartridge Case Life

Q: I have read that the life of reloaded cartridge cases can be prolonged by sizing only the necks, instead of resizing the cases full length. Just how much difference in case life does neck-sizing make?

Donald Lawrence

A: The experience of handloaders differs somewhat in this respect, apparently due to dimensional differences between sizing dies, rifle chambers and the chamber pressures to which the ammo is loaded. However, experiments I carried out have convinced me that case life does not depend upon whether cases are resized full length or not, but rather on the amount of working done to the brass. The only way to obtain long case life in reloading is to use a sizing die which nowhere reduces the case outside dimensions excessively.