7.62x25 from .223

[Battis]

I'm trying to form 7.62x25 from .223. I measured and cut the .223, then ran it through the die. The cases won't chamber completely (I removed the barrel to test). .223 headspaces on the shoulder (right?) and that appears to be the problem - the shoulder isn't set back enough. I tried two different presses, two different shell holders, shimmed under the brass in the holder. Could it be the dies?

[36g]

It should work. Do you know if the chamber on the barrel is properly cut (will a factory loaded round fit properly?). .223 headspaces on the shoulder as does the 7.62X25. Could be the dies. If it is the dies you could lightly grind the base of the sizing die to allow the brass to be sized slightly shorter. Or, get another sizing die...

For those people who shoot blanks through a subgun, the 7.62X25 blanks are typically made with .223 brass so making live brass should be similar only trimmed shorter.

[Kosh75287]

When you form the shoulder and case neck by running the cut .223 case into the 7.62x25 sizing die, what do you do about the thickened case neck? Do you have to ream the necks?

[Misery-Whip]

You didnt say you trimmed to final length after forming...

Measure your formed cases and compare to a print.

Who made the dies?

[muskeg13]

I haven't done this in almost 30 years, when no boxer primer brass for 7.62x25 was available. You should be able to make it work, but converting .223 brass is a LOT of work. Once you get cases to chamber, you're likely going to need to either inside or outside neck ream. The cut down .223 brass is much thicker than the necks of factory 7.62x25. Before I could obtain Starline 7.62x25 factory brass, I found that 9mm Magnum brass was easy to trim and form and didn't require neck reaming. 9mm Magnum brass is probably rare today, however...Graf's has PPU Tokarev brass available in stock right now. https://www.grafs.com/retail/catalog/product/productId/74481 Graf's also has both Starline and PPU .30 Mauser (not Luger) brass currently available that you can probably substitute for 7.62x25 without any problems.

[Battis]

The dies are Lee. I trimmed them to length with a Lyman trimmer.
Grafs has the brass but won't ship to me in MA, even when I use a NH address.
I have one vintage round that drops right into the removed barrel. I measured the outside neck diameter and it's the same as the cases I formed. I reamed out the neck on the five rounds I formed using a 19/64 drill bit.
What's strange is that I primed a few cases, chambered them one at a time, the slide closed, they went bang and ejected. The fact that the slide closed on an empty case makes me think I'm missing something.
Maybe they are chambering when the slide closes but not when I drop them into the removed barrel.
I have some Starline brass from Bayou Brass on the way that should answer some questions.

[36g]

For the cases that you primed, chambered and fired is there any indication of the case mouth starting to crimp in like a roll crimp that would indicate the brass being deformed in some fashion when the slide forceably closing on the case. Or any other dings or deformations on the fired brass?

[Battis]

I just primed a few more, dropped them into the barrel, and closed the slide. It closed even at a slow pace. They each fired and ejected. The primers aren't pierced, the brass isn't deformed or marked.
The problem is that I usually use a removed barrel as a gauge (if I don't have a cartridge gauge for that caliber). Bad idea this time. I think the cases are chambering (obviously if they fire and eject). User error...
I'll load some true dummy rounds tomoorrow.

[TyGuy]

I have played this game and ended up with usable cases. Like others have said, it’s a lot of work and the cases are not perfect. The case heads are a bit small (though not enough to cause extraction issues in my CZ), the capacity is less, and the brass is thicker. I found outside neck turning to work best for thinning the neck of the cases. Even after all that they still tend to be very tight in my CZ’s chamber. I have considered milling down one shell holder just for those dies to adjust the shoulder back a bit more (better to modify the cheaper part mentality). Once they are fired they fit much better but look like pregnant guppies. I have yet to try them in my Tok AR but it’s on my to-do-soon list.

I really just need to bite the bullet and get on Starline’s back order list…

[dtknowles]

There are easier ways.

[GhostHawk]

I made mine from .223 blank rounds that had thinner necks. So avoided a lot of the issues.

I also think bullet choice can make a big difference. I had issues with the lee round nose 90 grain handing up about 1/3 of the time.
Eventually I got and used the Lee .314 truncated cone nose tumble lubed design and all my problems went away.
I also bought some starline brass which did not hurt any.

[Battis]

Well, the empty cases chambered, fired and ejected, so I tried a cast bullet, sized down to .309 (the bore measured .3095). I seated the 75 gr bullets at different depths, crimped, even ran the dummy rounds into a .223 sizer (deprimer removed). None chambered. I'm getting good (and tired) of removing the slide, barrel and extractor. I'll wait for the Starline brass.

[gpidaho]

I had problems the first try at converting 223 to 7.62X25. Getting the shoulder in the right spot was my problem. As I had my dies in a Lee Classic Turret that is what I used to size the cut down 223. The Lee press is a great little press and I use it a lot but (mine at least) won't cam over solid enough to set the shoulder back to the proper spot. The shoulder was left about .006 long and I didn't have enough foresight to tear my Tok down and do a plunk test before loading up a batch. Changed out the FL size die to a Rockchucker and the problem was solved. Gp Edit: My Romanian Tok chambers .312 bullets with Starline brass

[WRideout]

I had a lot of trouble with my Tok not closing and locking when I first started reloading, even with factory brass. Then I discovered that I was applying too much crimp, which caused a slight bulge in the neck.

Wayne

[gpidaho]

I had a lot of trouble with my Tok not closing and locking when I first started reloading, even with factory brass. Then I discovered that I was applying too much crimp, which caused a slight bulge in the neck.

Wayne

7.62X25 was my first adventure into bottleneck auto loading pistol rounds and as Wayne said too much crimp can also cause chambering problems. Best to take an unsized fired round and take accurate measurements of the neck O.D. and shoulder placement and make sure your loaded rounds don't exceed these measurements at any point. This should give a couple thousadths clearance in the chamber. Gp

[Battis]

I read that some shooters use 9mm Mag brass to make the 7.62x25. I don't have any but I have 9mm Largo brass, which is close. I tried one - not so good. I'll just wait for the factory brass to get here.

[Battis]

The Lee dies are marked 30M on the expander/powder dies and seating die, but Tokarov on the sizing die. 30 Mauser dies are slightly longer than the 7.62x25 (7.63). If I have a .30 Mauser sizing die, would that explain why the shoulder isn't set back enough?

[mf79]

I found I have to trim outside neck and trimming inside was a pain so I ran them in 308 win die for the inside width then they would fit the outside neck trimming tool but the cutter head is longer than the case part that holds the bullet so I trimmed a 308 case outside neck and cut off about 1/8 inch and put it on neck trimming tool as a stop so I do not have to watch not to trim the shoulder.I also have an extra drill chuck that works well to hold the brass.

[dtknowles]

If you have a lathe, it is easier to just form 38 specials, trim to length and turn the heads and you end up with case that have the right head diameter. They also will have more capacity. I would rather turn the heads than the necks.
TEK

[Battis]

I'm thinking that the sizing die isn't reaching down far enough to push the shoulder back where it should be. I have one factory round that I'm using for comparison. The shoulder is definitely lower on the factory round than any I've formed from .223 (same case length). I'll wait for the Starline brass to get here before I mess with the die.

I'll try a .38 sp case (drill press time - I don't have a lathe).

[rbuck351]

Both my tok and my cz have very tight throats and barrels in the 311 312 area. I can't load a bullet larger than 308 even using real 7.62 x25 brass without thinning the necks. I have formed some from 38 spl cases and found them to work well but you still have to make sure you have proper neck diameter after the bullet has been seated.

[Battis]

I called Lee Precision. The tech guy told me that the sizing dies are exactly the same for the 30 Mauser (7.63 x25) and the Tokarev (7.62x25) despite the case length difference. My muddled brain thinks that the shorter case will not have the shoulder set back enough (and a shorter neck). He said to send the die back and they'll measure it out. Maybe.
I'm still waiting on the Starline brass. That will help with questions.
I tried a .38 SP case. It formed well and I gotta work with it some more.
I did a chamber cast that I'm still examining.
I ordered 50 rounds of Prvi Partizan. I gotta fire this gun.

[skeettx]

This will work

1. use an RCBS 7.62x25 trim die and an extended shell holder.
2. trim all that sticks up with a jewelers hack saw
3. final trim in Forster trimmer with a .308 Forster internal reamer
https://www.midsouthshooterssupply.com/item/00070nr1308/inside-neck-reamer-(point308-diameter)
4. full length size in an RCBS sizing die
Load as normal

Mike
4.

[DDriller]

If the sized case chamber but loaded rounds don't you need to inside ream the brass.

[Battis]

Sized cases don't chamber. Loaded dummy rounds definitely don't. Lee Precision also suggested removing material from the bottom of the die to set the shoulder back, though that will negate any warranty.
Starline brass will be here Friday. Hopefully that will work.

[Battis]

I got the Starline brass from Bayou Brass and Ammo, loaded up some dummy rounds, and all is good. They chamber and eject. Tomorrow I'll try loaded rounds.

[Battis]

Went to the range with PPU factory ammo and a dozen handloads (78 gr cast bullets sized to .309, 5 grs Titegroup). The gun handled everything perfectly (both mags). Out of 30 rounds, I only lost 3 cases into the ozone layer. Great gun to shoot- due to its heft, there's not much recoil. And it's as accurate as I let it be. Next time I'll bring the chronograph.
The military .223 brass is too thick to form and hold a proper shoulder. I'll ream and thin the brass before I try forming, not after. Reaming the neck isn't enough - the brass that forms the shoulder below the neck has to be thinned. Rookie mistake.