View Full Version : re-form 8mm to 7.62?
Deltaten
December 31, 2006, 17:09
Spoke w/justa the other evening when he *finally* got a line outta China; with the cable being sheared n'all.
Anywho.. he came up with the idea of puchasing vast quantities of Turk 147 gr 8mm cheaply, pulling the bullet, dumping the powder, re-sizing the case; pour in the proper amt of pwder and pop in a fresh .308 bullet.
Even went so far as to wonder whether a .323 ball could be squidged down to .308 w/o too much hassle(or cost ;) )
So I ask...
how tough would it be? I oughta go out to the shop and try it, just for S&G; but wondered if anyone else had been/was mad enough to give it a shot?
Only gotta push the shoulder back 4mm and trim the excess. Waddya think...two or three "stages" or anneal and do it in one go?
curious and cheap,
Paul
win308
December 31, 2006, 18:32
Problem 1..........it's corrosive primed. Problem 2.....you strain the gun/blow the gun shooting 7.9mm through a 7.62mm barrel.
Better solution: There seems to be plenty of 30.06 available. The bullets are the same size as .308....non corrosive primers.....boxer primers so the brass can be reused....and the brass is 50 years newer.
Having said all that, I once rebarreled an M-1 Garand to 8mm and shot cheap ammo for a long time. When I got over that, I installed the original barrel back on the Garand and sold the 8mm barrel at a gun show. (At the time, Garands were $121.00 from the DCM).
That's the way to go if cheap ammo is where you need to be.
Deltaten
December 31, 2006, 20:22
I dunno win; mebbe I missed something??
Even PS 30.06 is $.22+ a pop. Turk 8mm can be had for 'bout $.07
I don't care if it's corrosive. Most of my C&Rs are too. NO big deal.
Like I said "pop in a fresh .308 bullet...". **Maybe** see about swaging .323's down to .308 later.
As much as I'd **love** an 8mm FAL, I don't see much action in Stimpy's thread lately, and it's not real easy ta wedge an 8mm into an FAL.
Paul
ftierson
December 31, 2006, 20:30
I see no reason why this wouldn't work quite nicely (also using .308 bullets in the reformed cases, of course)...
I've swaged .30-06 cases to 7x57mm with no trouble except that you loose a fair number of cases to brass foldover (creasing) in the neck when going directly from .30-06 to 7x57mm in one step.
I doubt that you'd have much trouble with neck creasing going from 8x57mm to 7.62x51mm...
But it strikes me as a lot of work with a berdan case for just one shooting...
I'd just as soon buy some 7.62x51mm cases and reload them...
Forrest
ftierson
December 31, 2006, 20:33
By the way, I should also mention that Turkish 8x57mm cases would be fairly low on my list of 8mm cases to use for such an undertaking...
Earlier Turkish cases didn't have a good neck anneal (if any at all) and tend to split on first firing. As a matter of fact, they are often found split before firing. I have a feeling that they might also split when subjected to this case reforming...
The later dated Turkish ammo should display a neck anneal and should work better...
Forrest
fire for effect
December 31, 2006, 20:33
Swaging .323 down to .308 is to much. The copper springs back and you will have a loose core. the best you can do is .003 of an inch. So .311 is possible but not .323
Deltaten
December 31, 2006, 21:22
Thanks, gents. THAT's what I was lookin' for!
Happy New Year,
Paul
K. Funk
January 01, 2007, 09:33
.30-06 brass is an excellent choice to make 8mm, but like the others have said, too much work to go 8mm to .308. I agree that brass is readily available for the .308, just do that. A quick search turned up about a half dozen companies selling once fired brass.
krf
1006587
January 01, 2007, 10:19
The groove on the rim is very different. You may have problems with the extractor, it will stick out more and keep the bolt from closing. Not to mention less supported area at the back of the case.
It might work in a bolt gun, wouldn't want to try it in a semi auto.
ftierson
January 01, 2007, 18:32
Actually, Paul, your original question got me thinking about this...
So, I took five fired Turkish 8mm Mauser cases (1946 headstamped) and ran them through a RCBS .308 Winchester full length sizing die.
All five cases formed perfectly...
It would have been even easier with new, unfired cases.
The only problem that I had was that I pulled the lag bolts holding my Lyman Orange Crusher press up out of the table top on the fifth one.
That's because I'm stupid and didn't remove the expander plug (although I was smart enough to remove the pin for the berdan cases :)) which had to be pulled through a neck that was at least twice as long as a normal .308 one would be...
If you decide to try this, remove the expander stem before resizing, cut the case to length, and then run it through the sizing die again.
Now I need to get three four inch lag bolts to replace the three inch ones...
:)
Forrest
shortround
January 01, 2007, 18:56
You'll also have to either ream the neck or turn the outside. The farther down the brass you go the thicker it is. If you just size it, trim it and seat a bullet, it probably won't chamber as the neck will be too thick. If it does chamber, it may not have enough expansion room to let go of the bullet driving up pressure.
Bottom line, buy some surplus or once fired brass and reload it.
Corn Nut
January 01, 2007, 19:00
If you really wanted to try the unfired/new case thing with 8mm, just do them like a fresh shrimp. Hold the case with one hand and the projectile in other and give it a little tension. Put the tips of your thumbs together and put pressure there. Like you are pinching off the head of a shrimp.
mj2evans
January 02, 2007, 07:48
For the right price I would shoot corrosive 7.62 in a FAL. I just think this is a lot of effort for berdan cases. I would think the case forming/neck turning for one shot brass would make this economically unfeasable. But hey, if you can work it out I'd buy some.
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.