Before I talk myself out of another .40 I need to ask:

If someone was to start with the basic .405 brass how involved would it be to size it down for .408 bullets? What die would you use a 40-70ss? Then what chambering reamer would one use. The goal here is another option to say the 40-82 silhouette from 45-90 brass. I am planning my next Ballard build for BPCR long range shoots. I just love the 40-85 Ballard caliber, but acquiring proper brass and reamer is down right pricey. Have absolutely no interest in the 40-65. Any other thoughts on wildcatting a cartridge that approximates the 40-85 without overspending would be appreciated. Plan is to use a 14" twist and 425 creedmore gg bullet.
thanks
kw
kw

.408" seems a bit small for a .40-70SS? Or is that because you already have the barrel and it has a groove diameter for .408" bullets? My .40-70SS is a .410" groove, and I use .40-70SS Lyman die set in loading it. I also load for the .40-63/70 Ballard and use the same die set to reload fired brass. 
I've used my .40-65 Win. die set to neck size the same .405 Win. brass to make up ammo for my .40-63 Ballard and .40-70SS, but only after fire forming it first.
The .405 brass from Hornady is out of production, but it was a little small on rim diameter for use in my Ballard .40-63 anyway. I use it, but have to be careful chambering cartridges to ensure the rim doesn't slip past the extractor.
As for the .40-85, I use 9.3x74R brass expanded to .40 caliber and it's the perfect length as is. But it also has slightly smaller rims, and need to be careful to not let the rim slip past the extractor while chambering. But it works extremely well, and shoots great. If I was starting with a new build I'd simply have it chambered for .40-85 Ballard, but have the rim cut for the 9.3x74R brass size. Then it would be perfect.

It is noted that Winchester has made another run of the
M1895, in cal 405 Win.
It may very well be that due to that, Hornady might
make another run of their excellent 405 w brass
beltfed/arnie

KW,
I did a 40-82 W 1:16 in a Hepburn a few seasons back, made the reamer and just have to modify the rim on a 45-70 slightly - I tried my hand at extruding 45-70 brass - it's a shooter but comes with a lot of extra effort. 
 
I read about the Crossno 40-82 and before I came to my senses bought that reamer from Manson.  I'll use Starline 45-90 brass for this - (keeping it simple) I'm changing to a 14 twist, gain, LH  in this to make it different.  I'm doing a Ballard for the class demo this fall so this will be my subject.

Just my personal opinion, these are exceptional cartridges and to 1025 Yards I've had very good results with my first 40-82.  I'm loading some 444gr. Nasa for a shoot next weekend, preliminaries look good, but this will be my first go with this bullet.

I grabbed a few boxes of 405's at a show a while back, over-priced but I got them    If Hornady goes with another run I'd buy several and then I'll look at building something based on this. 
Greg

Kim,
Dave Manson makes the Crossno reamer and like I said I pushed the go button before I gave it any real thought... spontaneous purchase... no regrets though.  something different - it will be a second 40-82, how many does a guy need???  The gain twist... it's old - but probably a passing fad, just like smokeless powder  but it intrigues me - it's what I'm building on my version of the Robbins and Lawrence machine.   
If I was to buy another, I'd call Ron Smith at RKS  (403) 631 2405 and see if he'd build you one...
Greg

The 40-82 silhouette is an approved cartridge. As I said previously it is almost a dead ringer for the 40-65 Ballard Everlasting, a 2.4" 40 caliber case with a 45/70 sized head and rim. The brass was thicker and the neck was .435" diameter, which is .005" larger than the later 40-63. If Dave Crossno had done some research and called his cartridge a 40-65 Ballard there never would have been any question. His business is still in operation and has the reamer and could chamber your barrel for you.

Reverend Al wrote on Jun 26^th, 2019 at 1:40pm:


Al, my 9.3x74r case extract flawlessly in my Pacific in .40-85. It's chambering that gives me fits. I have to be careful chambering a cartridge to ensure the rim doesn't slip past the extractor and then not allow the breech to close. I've gotten used to it happening, and have a technique of pushing the extractor forward with my thumb as I feed the cartridge into the chamber. But I'd prefer to not have to think about it.
I have a small number of cases made from .45 Basic brass that have the correct rim diameter, and I love using those! But they take a fair amount of forming to get them down to .40-85, and the 9.3x74r is super easy to form.

KFW,
I looked in the safe one day and realized that it was taken over by a variety of .40 caliber single shot rifles? I'm unsure how it happened as I didn't seek out .40 caliber rifles really. I think I'm at around 8 of them now in various .40's from the little .40-50SS to the .40-85 Ballard. Couple of .40-85's, a couple .40-65 WIn., several .40-63/70 Ballard, and a couple .40-50SS Rollers. They all shoot very well at distance.
The .40-50SS is a newer caliber for me, and I've been impressed with how well it works with smokeless powders. It's an anemic BP caliber, and I'd guess that's why it never made it back in the BP era. But it's like a .38-55 on steroids with smokeless. The advantage of a larger bullet, but a small capacity case that's much more efficient with smokeless than most of the larger capacity .40 caliber offerings.

KFW,
I almost built a 40-82 Silhouette myself. However 
after working with my little 40-65, I dropped the idea:
You said you have absolutely no interest in the 40-65W.
For which brass is available off the shelf or easily formed from 45-70s.
However:
Here are a couple pics on what this "little cartridge that can
do", even at Long range when loaded with the right bullet.
I did build a 40-72W(405Hornady cases) as seen in second pic, third from left.
But, my go to rifle, even at long range is my 40-65 Hiwall,
16 twist.   
I do contemplate, however building another 40-65 with 14 twist barrel...