7x57 cases from 270 cases

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22to45

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I made a few this afternoon from scrounged range brass, to see which ones would hold the most powder etc. They went very easy in the press, they were decapped and cleaned, then the .284 expander plug was run through the necks, then the case was sized in the 7x57 die, then the expander plug again, then trimmed with a Lee trimmer in the drill press. The weights are of primed cases, and now I need to build a neck annealer, and I will be in business. My guess is that the smaller capacity cases would be better for faster powder, but it is just a guess....
Case MFG
Winchester Wieght of case 187 Grains of Water in full case 56.5 Comments made from 270 case
RP Wieght of case 194.8 Grains of Water in full case 54.8 Comments made from 270 case
FC Wieght of case 195.9 Grains of Water in full case 55.6 Comments made from 270 case
NNY Wieght of case 176.8 Grains of Water in full case 57.5 Comments fired, resized
Frontier Wieght of case 185.7 Grains of Water in full case 55.2 Comments made from 270 case
Gevelot Wieght of case 207.9 Grains of Water in full case 53.5 Comments Unfired


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While I form several different cartridges from varying parent cases the 7 x 57 from .270 is one I would never do due to very real safety concerns.

Even if your cartridge segregation is flawless there will always be a chance your modified cases will find their way into a rifle chambered for the .270. Thanks to the shorter over-all of length of the 7 x 57 they will easily fit in a 270 chamber and will probably fire which could result in catastrophic damage to the rifle - and shooter - as the .284" is forced down the .277 bore.
 
tiriaq said:
Will 7x57 chamber in a .270 rifle? Case is shorter, but neck diameter much larger.
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Yes it usually will dependent on the bullet used. The Maximum OAL of a loaded 7 x 57 round is .334" shorter (the maximum case length is .306" shorter) than the .270. That 1/3 of an inch sometimes gives enough room for the shorter round to chamber.
 
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OK I just measured a loaded 7x57 with a 175 grain spitzer loaded to maximum OAL. Using my .270 comparator on the round I measured 2.55" which is just over the maximum case length of 2.54" for the 270. As the chamber neck diameter is much larger than .277 there is even more room which probably would allow for a slight "crush" fit even in a chamber with minimum dimensions.
 
I had not thought of that, I do not shoot a 270, 280 brass would be ideal, but of course it does no show up at the range I shoot at, nor is it easily bought. that leaves using 30/06 brass, which is not as easy to size...
 
Enough of the theory. I did up a dummy round in new 7 x 57 brass using a 139 grain spitzer. In my .270 Win chambered M1895 it is easy to measure the headspace which is just over 5 thousandths of an inch.

2703.jpg
 
22to45 said:
I had not thought of that, I do not shoot a 270, 280 brass would be ideal, but of course it does no show up at the range I shoot at, nor is it easily bought. that leaves using 30/06 brass, which is not as easy to size...
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If you have a dremel tool you can use a small ball cutter to deface the "270" stamp on the case head. Just leave 3 small round dots where the letters were.
 
I remembered that I have a 270 here, so I put a 139 grain hornady boat tail in a case, and it will go inside the chamber, in fact it will go too far to hook the extractor on the mauser 270. I can see the mark on the case where it was pushed into the neck area of the chamber, I really doubt that a bullet .007 oversize would blow a rifle up, but I am not going to be the one to test it.
 
that is funny, we both did the same test.. I can make up a jig to deface the heads with a dremel.. I have a mill, a lathe, dremel etc.. I can deface. the heads.. I was surprised that it went in as easy as it did in the husqvarna 270 that is at the house... 7x57 brass is both a bit rare and a bit expensive. I am a bit of a hoarder, and would like to have 500 or so more...
 
'Boo said:
Enough of the theory. I did up a dummy round in new 7 x 57 brass using a 139 grain spitzer. In my .270 Win chambered M1895 it is easy to measure the headspace which is just over 5 thousandths of an inch.

2703.jpg
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Maybe it's just the lighting, but by the looks of the primer in that spent case, appears to have been a hot load. I do not have a 7X57 (but it does interest me) nor an 8mm so this may be a suggestion of ignorance, but is 8mm Mauser brass not more affordable than 7mm?
 
New Camper said:
Maybe it's just the lighting, but by the looks of the primer in that spent case, appears to have been a hot load.
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As it was a brand new unfired case with no primer it must be the lighting.

I don't think there should be any real difference in cost between 8mm Mauser and 7 x 57 brass. Today it usually all boils down to availability in the marketplace. Some manufacturers choose to ream shooters for "rare" casings. Nosler for example asks 3 times as much for Head-marked 338-06 cases than near identical 30-06 cases.

Some other cases are just rare and not easily formed from other rounds. A good example of this is 7 x 61 Sharpe & Hart brass. While the case can be formed from most other sizes of belted magnum cases there are a fair amount of cases lost during the re-forming. thanks to the cartridge's sharp shoulder.. Once you get a case formed down the necks still have to be turned and annealed. A couple of years ago I bought 50 of the last 7 x 61 cases ever made by Norma (they are now discontinued) and by the time I had them on my bench they ended up being close to $3.00 a pop! In retrospect I should have just bought the proper form dies for 200 dollars. ;) LoL
 
'Boo said:
If you have a dremel tool you can use a small ball cutter to deface the "270" stamp on the case head. Just leave 3 small round dots where the letters were.
Click to expand...

If you have a Wilson trimmer just shave the caliber stamp off, adjust your cartridge headspace to compensate for removed brass. I have lots of cartridges made from other rounds, clearly marked in MTM boxes.
 
New Camper said:
Maybe it's just the lighting, but by the looks of the primer in that spent case, appears to have been a hot load. I do not have a 7X57 (but it does interest me) nor an 8mm so this may be a suggestion of ignorance, but is 8mm Mauser brass not more affordable than 7mm?
Click to expand...

On Tradex's site, they list 7X57 Previ a being $5 per hundred less than 8X57 Previ.
 
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