Modifying Cartridge case

[BillPa]

I'd like to know the maximum length it will allow a case to stretch so that I can minimize case trimming. I'd like to keep case length within a reasonable distance short of what the chamber is reamed for. These are on Remington factory barrels with their typical long throats. Still kinda new to this and trying not to be too anal but just wanted to know how little I can trim length to and still be ok.

Personally, I'd just make a chamber cast then measure it. ;D

As well as the max neck length you can also measure the amount of freebore and chamber neck diameter using the same cast.
http://www.brownells.com/search/index.htm?k=cerosafe&ksubmit=y

Bill