What dimensions would you increase the 6.5 mannlicher case to, if you were to improve it?
original dimensions are:
head .452"
Shld .428"
neck 23.5 deg(very close)

How much body taper do you need?
It would be for a stack magazine,not rotary. Probably in a SA M70.

Interesting question.......because the Arctic explorer Villjmar Steffanson somehow "improved" the 6.5x54 MS for use in his MS 1903 carbine, but I have never (for last 15 years) been able to track down exactly what he did to the case and chamber. If anyone knows please holler.
One caveat involves the MS rotary clip...which reportedly is very difficult to modify (for subsequent cartridge delivery-to-chamber), should any changed cartridge be used.

I'd make it look the the Swede.

quote:

Originally posted by Woodjack:
What dimensions would you increase the 6.5 mannlicher case to, if you were to improve it?

You can't improve it. It's great just the way it is. roger

It is called the 6.5-284.

Jeff