Agreed, but with a caveat... Having communicated with Jandrey in the whitetail forum I know that one of the cartridges he has is a .300 mag.

To be honest, I've never loaded the .300 mag. That said, I started loading a 7mm RUM. The first issue that came up was case stretch in front of the head. The guy that was teaching me was trying to do a "partial" resize, and the shoulder wasn't getting set back. This quickly developed into a pressure issue that we would more than likely not have been detected right of way had we not been using his Chrony.

I can see the same type of issue happening with the .300 if the cases aren't being fully resized properly.

So as I said, I agree that a Chrony isn't an absolute necessity But based on my very first experience with reloading, and now realizing what could have happened, I'll never develop a load without one.