Saw a barrel in a shop today in this caliber. It looks like a factory barrel. Anyone have experience with this caliber? What’s it good for?

Varmint and small game caliber - 357 case necked down to .25 caliber.

For the Encore, probably was a TC Custom Shop barrel.

TC chambered the Contenders in .256, but it’s mostly a dead caliber.

Yea from the research I’ve done so far it looks to either be a pain or expensive to shoot.

Terry Wieland is a big fan. I'd go .25/35 myself and save some trouble, plus add some capabilities. For some the trouble is the attraction, which I get.

I have owned three .256 Winchester firearms: A Martini Cadet customized built for the cartridge (by someone else), a Marlin Model 62 lever action and a Contender with a .256 barrel. Still have the Marlin and the Contender. It's a bit of a pain to form brass, but if you neck size it once it's formed it lasts a long time. I found it to be pretty accurate out to 100 yards and minute of woodchuck out to 200.

The old 60 grain hollow point bullet was perfect for the case, doing about 2800 fps out of a rifle. I now shoot 75 grain hollow points at about 2400. You'd lose 4-500 fps out of the Contender barrel.

25/35 ammo I believe is only hand loaded.. you could go to 25 06 which would close to 25/35 and you can buy loaded ammo...( just my opinion)

Several ammo companies offer 25/35 Win ammunition.

My dad has a TC Custom shop Contender rifle bbl in .256 win. Also has a custom 14" pistol bbl ( non TC ).

Wondered how 85gr Nosler BT would work on deer kinda close.

Has a few boxes on WW factory ammo.
So reloading should be no big deal ( has dies ).

Unfortunately the rifle wears a lefty Fajen stock LOL

Got frustrated trying to make 256 from 357 mag brass. Ended up buying the form dies. Now it's a breeze.

Got a box of Win .25-35 ammo I'd give away to anyone with the chamber in one of their guns that lived in the area. Ain't shippin' it nowhere. I don't speak ORM-D

I had a Contender 10” octagon barrel at one time. Loudest damn thing I ever shot. With factory loads it had a huge fireball that I was afraid would set the grass on fire. Shot a coyote with it but just didn’t have a use for it so sold it. I would love to have a Ruger Hawkeye in it though

I have a 10" Contender barrel and a Marlin 62 in 256 Win mag. I've never come across any factory rounds. I annealed new Starline 357 brass and full length sized them. They worked fine in the Contender barrel, but didn't want to extract from the Marlin. I neck turned them and now the Marlin cycles fine. Fun round to play with. Cast lead 86 gr bullets work well and are super cheap. The Marlin really likes the 60 gr Hornady's at max.

I've tried forming using the seating die with the seater removed. Got so so results, still getting wrinkles. I need to try annealing to see if that helps before buying a forming die. I'm in the process of rebarreling a Rolling Block in .357 to .256. Can't wait.

My first attempts just using the full length sizing die left wrinkles and the few usable ones would split the neck upon firing. Annealing and using Unique sizing wax inside and out fixed that.

Good luck with your Rolling Block. Should make a sweet little varmint rig.