"Chamber recommendations for a Gain Twist .315 Groove Barrel"

Because this is not quite right for a normal (.321)  32-40 or a 32-20, I'm looking for suggestions for a American Rimmed Cartridge that is going to be a 200 yard light weight target rifle.....

I don't have a specific receiver in mind just yet.
I may re barrel a Martini Cadet or Uberti HiWall

Any recommendations..

TIA

Bob

I have seen 32-35, both Stevens and Maynard with 315/316 grooves. And a 32-40 Remington.

The line between 30 and 32 is pretty blurry.

I own an unusual Ballard that has a .32-40 chamber, but a 1:15" twist .316" groove barrel. I shoot it as a breech seater mostly, but I also size down .32-40 bullets to .317" and shoot it as a fixed cartridge occasionally. A little tricky crimping the bullets and not having bullets fall into the case before they get crimped to hold them.

First, Thanks to all for your suggestions... All of them are worth serious thought.

"A little tricky crimping the bullets and not having bullets fall into the case before they get crimped to hold them. "

My initial concern with the 32-40 was exactly what Val pointed out in his post above. 

I want to stay in the Rimmed 'Straight' American family of cartridges that utilizes brass whose parent case is generally available. This rifle is going to be passed down in the (distant, I hope) future. 

I am considering the 32-30 Remington (less case capacity and smaller case mouth) and the 32-35 Stevens / Maynard.

I would have a custom reamer cut by Pacific ($210.00)(6-8 week lead time) utilizing a otherwise readily available parent case.

Using that reamer to not only make the chamber but to cut a forming / seating die blank. And yes the dies need to be passed along with the rifle.

So to all that have gone down this rabbit hole before.
If this a good approach or plain silly.?

TIA

Bob

marlinguy wrote on Jan 25^th, 2026 at 6:46pm: