Need some help from those with a Lee 7.62X25 sizer

[Old Iron Sights]

I've posted here some time ago about trying to make reloads for my Rommy TT33. Never had repeatable success. After much trial and error, I've found my problem is not the cast bullet fitting the chamber. It's the re-sized case body itself. I recently acquired a Yugo M57 and it exhibits the same issues as the TT33, even worse. Problem is, my reloads won't chamber all the way. Factory ammo and loads from brand new brass are OK. This got me to comparing a new starline case with a once-fired resized starline and a once fired, unsized case. The only difference I can find is just below the shoulder. New cases are 4 thousandths smaller than once fired or resized casings. My sizer does nothing to the case body even though I run the shell holder all the way to the bottom of the sizer. I called Lee but they didn't offer much advise other than that I could mail in the sizer to have it checked. I'd appreciate it if anyone could tell me what their sizer works the case down to just below the shoulder. My top mark is .305 down from the case mouth and .086 down from the bottom of the shoulder.
74689

[Coyote3]

I checked some S&B re-sized cases and they're measuring .377" at the location you have mentioned. I am also using a Lee die set, but I am firing this ammo through a CZ 52 and the rounds are chambering fine.

In any case, the Lee die doesn't seem to be sizing the brass back to factory specs.

[khmer6]

I haven't had a chance to try mine out yet. I'll give ita go tomorrow and report back.

[9.3X62AL]

OIS et al.....

The 30 Mauser and the 7.62 x 25 are differing cases. These are subtle variations, but they are there.

The 7.62 x 25 Tok is .020" shorter in OAL, its shoulder datum line varies about the same, and cylindrical diameter in the Tok is slightly smaller (as your pistol has told you succinctly). I began loading the 30 Mauser for a C-96 about a year before buying a ChiCom Type 54 TT-30/33 variant in 7.62 x 25. Cases sized in the 30 MauMau die refused to chamber fully in the Tok. After chambering some dummy rounds with Magic Marker paint-up and seeing where the chamber was hitting the case sidewalls and shoulder, I called Huntington's, and was told the above info about the dimensional differences by a staffer. He recommended getting a 7.62 x 25-specific sizer die for the Tok, but that the seater from the Mauser set would work fine. The improvement in feeding was immediate and permanent in the Tok. Same story in the CZ-52, that came along another year or so later.

Also be aware that the ChiCom Tok chambers are cut to use .307" bullets stab-crimped into Berdan-primed brass, but have .311"+ grooves. My initial lot of 30 Mauser and 7.62 x 25 brass was reformed W-W 9mm Magnum brass. Bullets/boolits of the proper size for the barrel required me to ream the case necks to create clearance for the .312" boolits + thinned case mouth walls to clear and have release room. Starline brass does not require these reaming gymnastics, but does require use of the caliber-specific sizer.

If I had to venture a guess, Lee may be using 30 Mauser prints instead of 7.62 x 25 prints to develop their sizer dies.

[nwellons]

I have not had any trouble at all with my Lee 7.62x25 sizing die. All rounds chamber well. I'm also using a Romanian TT and shoot a Lee 311-100-2R boolit cast from COWW.

[Outpost75]

My Lee dies also size the case body to .377", rounds work fine in my CZ52.
74827

[9.3X62AL]

I have not had any trouble at all with my Lee 7.62x25 sizing die. All rounds chamber well. I'm also using a Romanian TT and shoot a Lee 311-100-2R boolit cast from COWW.

These pistols in this caliber show dimensional "poetry", for sure.

That Lee 100 grain RN has been a GREAT boolit in my pistols. I set a moderate roll crimp into the center drive band, and these cartridge run like water through the pistols.

[Old Iron Sights]

Someone suggested running the case through a 9mm sizer. That worked great. Only time to run though two mags today but they all chambered. They sized to 373 just below the shoulder. I also use the
lee 100 grain. When I get some rounds ahead I may buy a different sizer.