Home Forums Hunting & Shooting Custom Rifles & Wildcats 7X57 or .257Roberts to .270 wildcat

Ive recently been turned on to the .257Roberts and know that it is based on the 7X57 case. has anyone wildcated either the 7X57 by necking down or the .257Roberts by necking up to .270? if so whats it called?

thanks

There is no reason that I can think of to make a slightly shorter handicapped version of a classic cartridge that is already too slow. The action length you would need would be exactly the same and if I was going to build a 277 cal anything on a 30/06 length action such as what would be needed I would build a 270WBY without question. No reason to go slower when faster is available at no cost in action length and rifle wieght save for maybe wanting a little longer barrel which I tend to prefer anyway.

Probably has been done, probably works OK, but from here a great big YAWN and a quizzical WHY?

When it was done with a 277 projectile it was called Walter's Folly. Walter's the guy who tried it. Inherently inaccurate, wouldn't kill anything. And besides, he was driven from tha Garden of Eden for screwing up the 7x57 case so badly.

sounds like the guy must have had a lifetime's worth of 270 bullets and 7x57 brass

I think that is called drinking while building a 7x57AI...:)

checked Ackley #1 FWIW and not in there but there was a 270/Sav/303 but I can see those around an action...the 57 not so much.

I don't think you'd gain anything over the 6.8 SPC. If you insist on doing it, I've always found it less work to go up in caliber than size down due to thickening necks. You could use the Roberts or 6mm Rem.

Inland44,

As I'm sure you're aware, about anything that can be done to an existing cartridge has already been done. I am not a big fan of P.O. Ackley, but his books are invaluable for reference.

In this case he states on page 378 of Vol. 1: There is the .270x.257 Robts Imp. and on page 379 he lists the .277 ICL Flying Saucer. If I'm not mistaken, the ICL cartridge desingns have a 45 deg shoulder.

GH

As an aside, I wouldn't put a whole lot of credence in Ackley's loading data, he's been known to load VERY HOT!

Ed,

You are obviously a fool! Heck, everybody knows that POA's data is spot on and not subject to the usual laws of physics! If you "AI" a case, you increase capacity, reduce pressure, and make the case stretchless. For a man of your age and experience, I'm surprised that you don't you know nothin' about the wonders of POA!

JEff

PS - Just in case you didn't get it, the above is 100% TIC!

I would call it a waste of time and treasure.

The 0.07" difference in bullet diameter isn't going to make a 6.8x57 a most efficient, effective, or useful cartridge than the time proven 7x57.

JEff

The best use of the 7x57 case was the 6mm Rem.

The best use of a 7X57 case is to stuff a .284 bullet in it and go kill something.


Terry

my mistake on pp378

I have never understood why someone did not neck the 7MM Rem. Mag. case down to .270.

Probably would not be as effective as leaving the 7MM caliber as is, but I still wonder why someone hasn't done it, if they want a .270 and need more speed than the .270 Win. and don't want to go to .270 Wby.

It might have been tried, but was not publicized that much.

Thanks for all the input, just a couriosity. The minor gain or loss between the .257 Roberts and the 7X57 would be minimal but just wondering of at one point it ever had a following. I did see a website deticated to the 6.5Roberts and 27Sooper(or someting to that effect. Im not a handloader or a wildcater but I am intriuged with the tinkering that can go on between bullet diameters and existing cases...carry on.

I knew a guy back in the 80s who built a custom Mauser
and chambered it for a wildcat made by necking up the
7x57 to 30 caliber. I didnt understand why he did it,
but to each his own.

FWIW...

If a guy loaded the 270x57 wildcat to 270 pressures, it would be a pretty impressive performer...probably right along the lines of the 7x57AI.

+1. Same goes for the 257 Rbts.

according to C.O.T.W. the Chinese had their own caliber for their mausers....6.8x57. So, nothing is new....especially when it is a 100+ year old military cartridge.

advntrjky

I agree it's a turkey. I have a 7mm Mauser and it will do about anything that needs being done. I have necked the brass down to 274 Roberts, then fireformed it to the Ackley Improved version, also necked it down 6mm Remington for my custom Model 700. All that did was produce a bunch of cases that were head stamped wrong and had to be labeled carefully so they didn't get in the wrong chamber (except once fireformed the Ackley was fairly easy to distinguish).

How about the 270 Winchester Short Magnum if you want a shorter action - Winchester still chambers the M-70 for it, and a custom builder - well anything goes. Otherwise the original .270 Winchester is still as good as ever.

If I just had to have something between a 257 Bob and a 7X57, I'd build a 6.5X57. It's a very effective (though scarce) factory round.