I have a Ballard in 40-63 Ballard (same as the 40-70) that had a bad bore, so I put a liner in it and chambered it, and the Hepburn I’m building, in 40-70ss using a reamer that used 405 brass.

That being said, I now have brass that was already formed for the 40-63 Ballard chamber.  I believe it was a metric brass but if you are interested I would probably let it all go.  

I just looked, and found I have notes here in the house that say I have 48 that were formed from 9.3 x 74R brass. 
Bob

The closest rim and base diameters are .30-40 Krag, and .303 British, but both are short and require stretching a fair amount. BACO was selling .40-70SS or the Ballard version made from stretched .30-40 Krag brass as it's longer and requires less stretching.
I use .405 Hornady brass and it just requires less than .10" trimmed off to fit my old guns. I also have a huge amount of 9.3x74R brass I use for my .40-85 Ballard and it can be shortened, but both base and rim are slightly smaller. After fire forming the cases fit the chamber fine, and eject fine, but can sometimes slip past the ejector when chambering, so have to be careful inserting a cartridge. I don't use them for my .40-70's as I have a whole lot of .405 brass, but I would if I didn't have .405 brass.

mrballardman wrote on Aug 13^th, 2025 at 2:40pm:


I didn't see any mention Bob or I having any .40-63 Ballard cases for sale? I know I'm not selling any of mine!

mrballardman wrote on Aug 13^th, 2025 at 2:40pm:


I missed that you asked about the 40-63 brass.  Let me see what I actually have, I need to find them.  I’ll get back with you tomorrow by PM.
Bob