In other post I just obtained Ballard in 40-65 Everlasting.  What can you tell me about reloading those cases?  Do you resize them or does bullet just slide into the case.  Do they expand enough  to seal the chamber?  Inquiring minds want to know.  Anybody have one they would sell?  I have shot it with 405 winchester brass but it is way too at the mouth and body,  it is just not right.  Charlie

I use .405 Win. brass for my .40-63 Everlasting and it needs trimmed slightly to fit. It's much closer to the .405 in dimensions than the .40-65 Ballard is, so works great. 
Both .40-63 and .40-65 are the same 2.38" length, so both need trimmed when using .405 donor brass. But with your larger base diameter, and larger rim the .405 brass is going to be sloppy in the chamber. Closest donor brass that would be easy to use is .45-90 Sharps. It's very close in every dimension, but also tough to find until Starline decides to do another run.
I've had great results using 4198 powder and bullets anywhere from light 330 gr. to 410 gr. Somewhere around 23 grs. of 4198 is very accurate, and also mild at under 19,000 psi.
I never resize any of the brass for my single shot rifles unless it's new brass and needs a first sizing. I slightly bell cases to seat bullets and then taper crimp just enough to remove the bell. Whether yours could ever push seat a bullet depends on groove diameter. And they vary quite a bit among the Ballard .40 caliber barrels. Most run around .410", but can be as small as .407" rarely, or up around .412" also. Need to slug your bore to know, and then maybe do a chamber cast or just try the right size bullet in a case to see if it might push seat and chamber. None of mine will push seat, but mine are all .410"-.411" groove diameters.

PS-You could put one wrap of scotch tape around the base of a .405 case to help center it and then fire the case with a good charge to see if it expands enough to fit the chamber better. Depending on the cases, and chamber this sometimes works well and then remove the tape after firing and the case fits better. At least until some .45-90 cases appear for sale.