Craigster,
????????? I seat a 7mm bullet .284 in the case that is one 7mm caliber into the case, about half way down the neck..that requires a long magazine box, and a long throat in your chamber.
On a 257 Robts I will seat the bullets .257 deep into the case and again that equates to one caliber deep..
It is basically the same as improving the caliber without blowing the shoulder out and without having to rechamber some guns..
BTW a Short action Mod. 722 Remington in .257 Roberts can be lengthened by substituteing a Rem 721 30-06 or 270 magazine box..thats a pretty simple, inexpensive fix..Also applies to the pre 64 Mod. 70 Winchesters..
