Hey guys I'm thinking of having a custom single shot rifle with a falling block action built and I'm leaning towards a 256 Win Mag. Looking for info on loads, accuracy, and velocity from a 26" barrel. Any advice setting up a chamber for the 75 gr Hornady VMax and formed Starline brass? Would like to every once of accuracy from this round. Please share your advice & experiences. Thanks,
Alan

i have one in a martini cadet. being one of my favorite actions it met with the 256 very well. I've never used 75 gr bullets because the case capacity i think if a bit small for that. 60 gr bullet with 16.5 gr of IMR 4227 works well for me. I use the hornady bullet because its about the only one out there and I'm not fond of it because its a flat point. speer used to make a dandy 60 gr spitzer but hasn't for a long time now. can't tell you about starline brass I've only used win. but the load above has been my standard load for something like 35 years now.

Have you thought about a 25/20? Might be a little easier to find brass for and the longer neck would be nice should you ever want to play with lead bullets.

I also have a Martini Cadet in 256 Win. It's a great little cartridge with quite a bit more punch than the 25/20. Cases are easy to form from common 357 mag brass with one pass through the 256 FL die.
If you don't reload then the 25/20 might be a better choice but the 256, IMO, is a much better small 25 cal cartridge. 357 mag brass is stronger (and thicker) than 25/20 and lasts a long time. One "tip"...previously fired 357 mag brass is very likely to split during forming if it has not been anneled. New brass almost never splits. I guess the high pressure developed in the 357 mag work hardens the brass and makes it brittle.

I used to shoot 'chucks and turkeys with a Marlin 62 using 60 grain Hornadys for the 'chucks and 86 grain Remington 25-20 bullets for the turkeys. I think that you can often find new 256 Win Mag brass on Ebay, if you don't want to make cases from 357 Mag.

Jeff

i converted a savage 220 shotgun to a rifle in 256 win mag. i have found making cases fairly straight forward. use new brass 357 magnum cases in the sizing die with imperial wax lube. everything comes out ok.

I had one on a Martini Cadet action for a couple of years. It shot well with original factory ammo and even better with 75 grain spitzers. By well, I mean 3/4" at 100 yards for 5 shots off the bench, consistently.

I got about 2400 fps with the 75 grain bullets, which is a good deal better than a .25-20 will do with the same weight.

I sold the gun to raise money for a double rifle. If I had it to do over, I'd still have the Martini and just reached deeper in my pocket for the DR.

You could go a short step up to the .256 Max. Since you are going to have to form cases anyway, you might as well form them from .357 Max cases.