DWS,

In my view the 40/65 is a better choice by reason of component availability.

The 405 will require the 405 case, more expensive than the 45/70 sized to fit your 40.

The 40 has many bullet designs available for your use in times to come. Whatever it is you ulitmately decide to do with the rifle 40 will be more versatile.

Good morning,
Forrest

DWS, 
     If you like the long straight cases like the 405 Winchester. Take a look at the 40 Sharps Straight series of cartridges - 40-50SS (1.88 Inches long), 40-70SS (2.50 inches long). The 40-70 looks a lot like the 405 and brass is available from Rocky Mountain Cartridge Co. (You need to Login or Register to view media files and links) . Only qualifier is that the Bore size be the same as 40/65 .406-.408” so it will take the many bullet mould designs available for 40/65. Also requires that the chamber reamer pilot and neck size be correct for the .408” bore size! Some of the reamers are made to use 405 brass shortened to go in the 40-50 & 40-70SS, make sure you know which reamer was used to cut the chamber so you get the correct brass. The 3 ¼ inch long 40-90 Sharps Straight is another choice, personally would not fool with this cartridge for a smokeless rifle, but it should be very good in BP.
What ever you decide enjoy your new rifle, could not think of a better Christmas gift.
Mike  

The 40-70 SS is almost identical to the 405 WCF, only minor dimensional differences. It normally uses a .408 bore size like some 40-65s, and heavy .408 jacketed big game bullets are available if your thoughts run that way. I would choose the 40-70 SS over the 405 because of much better & far more versatile bullet selection, but would choose the 40-65 in 408 bore size above either of the straight cases because of its proven excellence and abundance of good loading data.
JMO, good luck whichever, Joe

Joe,

  Yeah! I'm leaning toward the 9.3. It'll be a coupla months before I've got the money, so in the meantime I'm blowing hot and cold about it and the .45/70. Just a case on if I chicken out between now and then. 

  What I'm planning on buying is the Pedersoli Kodiak Mark IV. Talked a little with Dick Trenk about it and found that the .45/70 is proofed at 35,000 PSI and they use the Federal 405 gr. load for regulating it. Dick says he's talked to several people at the shows who own them and they all seem to think they are a good buy. But would like to talk to someone else who actually owns one. Should probably ask on the Double Gun BBS.

  I see Buffalo Arms has 9.3 cases for $80 a 100, I think it is. They don't mention what brand they've got, but from the price I don't think they're making them from something else. Dies are $45, which kinda surprised me as I thought they'd be in the obsolete category even tho it's still a reasonably popular cartridge yet in Europe and Africa. I also see that NEI has a few suitable moulds to.

  Hmmmm. Never thought of the .405 as a possible basic case for the 9.3. Guess I'll have to see what the dimensions are for both.

PETE

OK if I understand this correctly:
The 4070 sharps straght is a longer straight case--(nominally with 5 gr more BP as originally loaded than the tapered 4065.) but it will take all the same bullets as the 40-65.  so this would simply involve cutting a new chamber in a 4065 barrel.  4070 ssharps cases are available. 

the .405W has to have a larger bore--and correspondingly larger bullets.   

Sounds like the 4070ss is having my cake and eating it too.   where is the downside--gotta be one there somewhere?

beaucoup de cool !!!!!!!  I think it'll be the .40 SSharps  a properly antique but very versatile cartridge.  I WILL remeber the reamer offer

and a Merry and Safe Christmas to all.

All wrong, please...  The Wesson action is basically the same as an Alex Henry action, so would be correct for an english sporting rifle.  BUT a brit sporting rifle should be chambered for a brit round!  No way around it...  Something like one of the .400 nitro's (the long 500/450 comes to mind - was available back then as a BP number in the days of the External-hammer AH rifle) would be good as well as authentic.  Brass will be a bit more expensive, true, but at least the rifle will be correct!