Is this a good conversion? Is it as simple as running the 8x57 into a 7x57 sizing die?
Is this a good conversion? Is it as simple as running the 8x57 into a 7x57 sizing die?
Yes, but check case length and neck thickness.
No 8X57 cases are not that easy to come by.
You should use easy to find .270 Win cases. Not that many people load .270 and the once fired neck is exactly the right size for 7X57. All you do is push shoulder back and trim to length.
EDG
I found these Privi Partisan cases at the range today. I have a '93 Mauser. I only have one box (20) cases for it, other projects occupy me. I have considered getting a form die but again, the rifle has been on the back burner. I read of using 270 cases when I was looking into a form die and actually have a fair amount of 270 cases on hand, I was collecting them to reform for a 280 Remington Encore barrel. I have not made any 7x57 from them as i figured the case was too long with trimming to length first. Would that be the best method?
257 Roberts will neck up to 7x57
so will 6mm Remington, and 6.5x57
6mm/244 Remington, 6.5x257 and 257 Roberts are all based on the 7x57 case necked down
I have a 9x57 Mauser and neck down new 9.3x57 to make them, that works really well and easy. try to start with only one size off either way, in your case 6MM Rem or 8x57
as you neck down a larger case that is many calibers/mm larger, it will grow longer
you can make 7x57 from common 270 Win, 280 Remington, 30-06 brass, by trimming some off every case.
personally I hate trimming a lot of length from cases, it takes the fun out of reloading, and takes up a lot of time usually- unless you have a motorized trimming tool.
I removed the crank handle from my RCBS trimmer and chuck it up in a drill to speed things up a bit.
there is also the 7.65x53 which will neck down to 7x57 but will be on the short side. the end result will fire in the 7x57 and you won't have to trim it for a long, long time and several reloadings....the bullet will have to jump into the rifling.
per previous reply, 8x57 is the best bet but those are not easy to find on the cheap boxer primed- the old wartime milsurp stuff is all berdan corrosive primed. if you buy that bulk milsurp 8x57, you can pull the bullets, powder and resize it down to 7x57, and reload it with powder, 7mm bullets again. the same thing going up from loaded 6mm to 7mm
Last edited by CaptainCrossman; 05-28-2017 at 09:58 PM.
I have an old Forster trimmer that I use with a drill.
A 5/16-24 carburetor nut or high nut fits the handle thread. I use a nut driver in the drill to turn the trimmer. You need a bit of patience but you can just make chips out of the over length .270 cases.
I have also made 8X57 and 7.65 Mauser cases from both 30-06 and .270 brass. It takes a good bit of work to trim 100 cases using my trimmer but you only have to do it once.
EDG
7x57 brass is easy to find. Why go through the trouble?
just make sure you full length resize down all the way, when making 7x57 from longer brass. back when I was 14 years old was hunting with a Ruger M77 7x57, my Dad made a few 7x57 cases from 30-06 military brass. a herd of doe ran by during doe season, I shot ahead of the lead deer too far and missed, then the gun jammed on me when I tried to chamber 2nd round- the milsurp brass would feed in, but the bolt handle refused to cam down and lock. I ejected it and tried again, same thing happened with 3rd round- by the time I got the 4th round to close, the deer were just tails and I flung a shot at them and missed. picked up the brass, the ones that jammed were the reformed milsurp 30-06 brass. they were full length resized and trimmed to spec. the 2 that fired were bona fide headstamped 7x57 brass. learned a valuable lesson, if you resize brass shorter from a full length 30-06 family case, down to the European 57mm case, make sure you full length resize, trim- and most importantly, take the gun outside and cycle the loaded ammo through the action to make sure it closes and locks on the resized rounds. this is something Jack O'Connor always recommended doing before going on an expensive mountain hunt or safari. take nothing for granted. sometimes the shoulders harden working the brass, and even though the shell is FL resized and trimmed, the bolt won't close regardless. had I known then what I know now, I'd have all working brass in the magazine. but what does a 14 year old kid know. BTW I still have the rifle 41 years later, and there's not a time I take it out of the case, that I don't think of that.
Last edited by CaptainCrossman; 05-28-2017 at 10:33 PM.
(chuckle...) so true !! I have a Tupperware can full of milsurp 7x57 in the basement, that I paid 33 cents a loaded round for. I've been giving it away to my nephews 50 rounds at a time for years, when they go shooting. it's milsurp with lots of corrosion and FMJ tips, but it shoots.
I run 30-06 brass into an old Pacific file/trim die (this pushes the shoulder back nicely), cut them off with a hacksaw then file them off flush with the top of the die. The result of this first step is a more or less formed case. I then size them f/l and do a final trim in a case trimmer. None of the rifles I have in 8x57 require neck reaming or turning. You may be able to make 7x57 brass from .270 brass using this method. At any rate, a file/trim die is a great way to remove a lot of brass in one fell swoop.
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I think the best way to trim a lot of brass from a case is to use the little tubing cutter Harbor freight sells for 35 bucks. I also like the Lee hand trimmer to square up the case mouths. you never can get them exactly straight with the tubing cutter, so I cut them (270 win cases) a few thousandths long, run them through the full length sizer die, then use a drill press and press vice with the Lee trimmer system to take off the excess length and square up the case mouth. it will always be square because the case is turning, like a lathe, and it's faster than chucking the cases in a lathe. the other nice thing about the Lee system is that if it happens to be a case the Lee doesn't make a guide rod for, I just make one on the lathe. I form 577 snider, 450/477 martini henry, and some other oddball cases this way.
It seems to me that alot of people that reform brass to a different case and caliber forget the cardinal rule about the finished case - try it in your rifle for function. I always dry run all the ammo I will be taking on a hunt, no matter how trivial it may be I don`t want a feed problem to happen when `Bambi`s` great uncle `Old Mossy Horns` steps out in front of me.Robert
Not so much where I live, not arguing, just stating a fact.7x57 brass is easy to find. Why go through the trouble?
claude
then run with what you have, based on your own needs. if you have 8x57 neck it down to make 7x57, if that's the rifle you have. I would not resize a lot of it, cuz eventually I think you'll run into 7x57 brass on the cheap.
such as this
http://www.gunbroker.com/item/651475321
Any if your looking for 270 brass to resize. I have some for .20 each plus shipping.
If anyone has 257 Roberts I would trade.
Right now a new .257 case is worth about $1.00 each.
Your recommendation of 6mm Remington is a mistake. The 6mm has a different shoulder angle and a different gage point. If you use 6mm brass you will wind up with excessive clearance in the chamber exactly like excessive head space.
http://members.saami.org/ManualsStds...0Remington.pdf
http://members.saami.org/ManualsStds...m%20Mauser.pdf
EDG
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |