I have a Ballard Pacific in 40-85 and shoit it with 9.3  x 74R cases blown out to 40 cal.  I load with 83 gr of 1 1/2 swiss under a 340 gr paper patch bullet. It shoots like crazy.  I also shot 400 gr lubed bullets but it prefers the paper patch...or maybe it is me that prefers it.

I don't think there was a 9.3x63 rimmed cartridge. There was a 9.3x65R Brenneke and a 9x63R.

Well, I have been working on forming the 9.3X74R case into .40-85 Ballard.  After fire forming a few cases, I attempted loading them. I was using .40-65 dies to expand the case mouth and immediately found that the expander would not go into the case very far before the case walls would bulge (buckle) below the expander.  I cleaned the case interior and even tried dry neck lube with no improvement. The expander would not enter far enough to reach the flairing segment. To remedy that, I used a  smaller expander and carefully just "kissed" it to obtain a small flair.  Next problem was when seating slugs longer than the distance the expander went in, the case would bulge below the bullet and prevent it from chambering.
Some cases were just fire formed; some I annealed and both had the same problems.
I had attempted to modify the cases by progressively expanding the mouth. The first one went okay, but every subsequent one expanded off center.  These I then fire formed, but the case mouths were extremely uneven.
The brass I have is Norma. Maybe it's too hard; too thick?   
I was able to get eight rounds loaded so they would chamber.  I fired these with a 335 gr. slug, a moderate powder charge and some COW to take up the air space. All fired nicely. I thought these cases would be easy to reload, but the same problem persisted with case bulging below the seated bullet preventing it from chambering.  This occurred with both annealed and non-annealed cases.
I have a feeling the chamber on this rifle was cut tight (too tight?) as fired cases won't accept the expander nor new bullets.
Plan "B" is to convert this into 40-65.  I don't shoot BP, so I don't need the case capacity.  I have those dies and brass.   
Frustrated.

Marlinguy,
I'm wondering if it's the Norma brass.  Seems no matter what I do or what procedure is used the brass bulges below the expander or the seating bullet and prevents chambering.
I see Privi is making this metric case; any guess it might work better?
Thanks for your input,
Mike.

PS-If it helps, I can measure wall thickness of my Nosler brass, both before and after expanding?

If you are firing it with a bullet you should probably use a full power load to fully form it. Here's a maybe: what if the chamber has been cut strictly for breech seating? Have you made a casting? what is your groove diameter?

I annealed my cases expanded them by fire forming  them with unique, corn meal and tissue paper and barrel pointed up to the sky.  Then I expanded them for a bullet, sized in a 405 win die to make sure there is no bulge, the loaded with black and fired.  Now they are good to go.  My ballard has a tight paper patch chamber so I shoot soft smaller dia paper patched bullet.  I can shoot full size grease grove bullets but it is snug, and if there is any belling and they won’t fit.  I don’t resize between loadings.

I followed Val's advice a couple of years ago and fireformed my 9.3x74R cases neck expanded to .40 and trimmed to .40-70 Ballard. I use 70% charges of Trail Boss, 350 grain cast and shot better than I expected from the unformed (preformed?) cases. Never had a case failure.

Yesterday I used the same procedure with .40-50SS formed from .303 British (9gr Trail Boss and 240 grain cast) and shot under 1" at 25 yards out the back of a friends barn (private range). The cases formed very well. I say skip the middle step and have more fun.  Thanks Val. Wayne