i have this old danish kraig rifle, in 8x58RD or 8x58rimmed danish.
couple of questions.
i see some stuff on buffalo arems regarding brass with two different thickness. one is .60 the other .70.
they are pretty insistent about the right size, to headspace.
does this really matter?
I have read where people are using 8x56 hungarian brass to fireform to the danish casing. Anybody do this? I have a bunch of the 8x56 the reason for asking.
at one time rcbs and lee were making the die sets. Didn't see them listed either place. Any thoughts other than going through buffalo?

Cartridges of the World will have drawings of the original case dimensions, and info on interchangeability and velocity and known loads. Other than that I don't know anything. An odd chambering in a Krag I've never heard off.

From Wikipedia:
https://en.wikipedia.org/wiki/8%C3%9758mmR_Danish_Krag

Ron, that particular cartridge went through an almost bewildering array of changes, as the Nordic rollers advanced from the preliminary metallic cased era, ....and forward, into the smokeless era.
There were, (and I've measured and chamber cast em',) 8 X 56, 8 X 57, and 8 X 58 reamers used ,...the shorter chambers generally the earlier variants.
The change from the .60" Rim thickness, to the .70" was directly related to the later variants, and is a relatively simple thing to figure out,....some shimstock and a set of calipers all that're required.
Get hold of this book, and, as well, get hold of my friend Croft, to discuss just what exactly you have,....he'll steer ya' straight. When it comes to getting this particular, and VERY popular European cartridge to perform properly, .....he's probably this country's leading authority.
Say hi to him for me, and wish him a Shiner Bock.

Link: http://www.morganprinting.org/RecentSingleShotMilatary.html

This one here's gonna be worth laying in, as well

Link: https://books.google.com/books/about/Restoring_and_Shooting_the_Antique_Singl.html?id=qDeBAAAACAAJ