Tales from the Back Creek Diary – the CZ52 in 7.62x25mm
© 2014 – Ed Harris
I picked up a surplus Czech Cz52 pistol chambered for the 7.62x25 cartridge. This was an impulse purchase, because the gun was like new and cheap. I already reload for .32 ACP, S&W Long and H&R Magnum. The same bullets and powders will work. So why not?
The 7.62x25 Russian cartridge is dimensionally similar to the .30 Mauser round used in the M96 Broomhandle pistol, but operates at higher pressure, about 40,000 vs. 30,000 psi. Both rounds fire the same .308-.309 diameter 85-87 gr., FMJ bullet, but Soviet "burp gun ammo" is too hot for an old M96 broomhandle. New manufacture Sellier & Bellot ammo chronographs about 1700 fps in the Cz52, whereas new Privi Partisan (PPU) gets a little over 1400 fps. By comparison the .30 Mauser round does about 1300 fps, and functions sluggishly with occasional "smokestack" jams when fired in the Cz52 pistol.
Hatcher's Textbook of Pistols and Revolvers (1935) described the .30 (7.63) Mauser round as developing 1250-1300 fps with various US ammunition and up to 1400 with WW1 German military loads. Penetration was eleven 7/8" pine boards, versus 4-1/2 boards for the .32 Smith & Wesson Long, 5 boards for the .32-20 Winchester, .32 ACP, .38 Special and .45 Colt M1909 revolver. The .45 ACP and .44-40 each did 8 boards. The .38/.44 High Velocity, 9mm Luger, and .38 Colt Auto each did nine boards. Only the .38 Super Auto and .357 Magnum were able to match the Mauser's eleven boards.
As luck would have it, by the time I received my Cz52 pistol, the once plentiful and seemingly “endless” supply of cheap surplus corrosive ammo which I had planned to hoard had dried up. People tell me that the quality of most surplus ammo in this caliber is poor, and that I really didn't miss out on anything. I was told that new commercial ammo is much better. So, I bought 500 rounds each of new manufacture PPU (Yugo Privi Partisan) and Sellier & Bellot (Czech) FMJ ammo with reloadable boxer primed cases.
Firing PPU ball ammo outdoors at 25 yards the gun shot to point of aim. An average of ten 8-shot groups averaged 3.5 inches, with the largest group 4.6" and the smallest 2.9" This level of accuracy compares to most typical military handguns firing service ammunition. At 100 yards in three trials I averaged 6 hits out of 8 shots on an Army E Silhouette firing from a two-handed sitting position. Both original magazines worked fine, as did also two Triple-K spares which I bought at the same time from Cheaper Than Dirt.
PPU ammo chronographed 1414 fps with a standard deviation over a 16 round sample of 32 fps. I was told by the importer that PPU ammo in this caliber is intentionally loaded down “so that it will not blow up a sound M96 Mauser if used inadvertently” – but the practice is still NOT recommended.” Czech S-B ammo gave accuracy and point of impact similar to the PPU, but shot flatter, giving 1699 f.p.s. with a standard deviation of only 7 fps over a 16-round sample. Impressive stuff to buy for your "Zombie Hoard."
I then started to experiment with reloading the 7.62x25, because I now had empty boxer rimed brass and hoped to accumulate more. Most of the S-B rom rounds I fired brass is still in low earth orbit over Ohio, but a useful amount of the PPU stuff was found up to 20 feet away from the firing position. New cases are available from Starline, and are of good quality, so I bought 500. These are really nice.
Years ago I loaded successfully for the M96 Broomhandle, using RCBS dies, the Lyman #313249 bullet for the .32 S&W Long, with 5 grains of Bullseye, as recommended by Lyman. I bought new Lee Dies for the 7.62x25, Federal 200 (small rifle and magnum pistol) primers and some Hornady .30 caliber 100-gr. half-jackets. Fired cases resized with little effort. Case mouths were flared easily and the Hornady half-jackets loaded without difficulty. Overall cartridge length was 1.378 inches. A Lee factory crimp die was used and rotor #9 in the RCBS Little Dandy Measure.
I load 5 grains of Bullseye as a “standard charge” in many popular calibers: +P in .38 Special with 110-grain JHP, a plinker in the .357 Magnum with any cast bullet, and a full-charge, lead-bullet load for the .44 Special, and .45 ACP, and a cast bullet small game load in almost any .30 cal. To 8mm rifle cartridge from 7.62x39 or .30-30 to .303 British, 8mm Mauser or .30-‘06.
With my “standard charge” of 5 grains of Bullseye in the 7.62x25 with the Hornady Half-jacket, velocity was 1240 f.p.s., with a standard deviation of 12 fps over a 16-round sample. Point of impact and grouping compared to ball ammo, averaging 3.8" for five consecutive 8-shot groups at 25 yards with the largest group 4.5" and the smallest 3.2"
Firing into water filled milk jugs the Hornady half jackets appeared to have expanded little, if at all, as none were recovered, perforating and exiting my entire stack of milk jugs, 48 inches of water in all, the same as ball ammo. Brief trials with 88-grain flat nosed NEI #82 cast bullets same as I use in the .32 Auto, gave 1330 f.p.s. with 5 grains of Bullseye and three of five bullets were stopped in 48 inches of water, with the others exiting. This equates to about 30 inches of gelatin penetration, impressive by any standard.
While Sierra and Hornady make .308-.309" diameter jacketed softpoint bullets suitable for loading in the .30 Mauser and 7.62x25, I was reluctant to pay 25 cents a pop to experiment. Instead I took an extra Lyman #3118 double-cavity, flat nosed .32-20 mold and sent it off to Erik Ohlen at Hollow Point Moulds for modification. The 88-grain NEI #82 gang mold I use in the .32 ACP and .32 S&W Long resembles a shortened Ideal #3118, which weighs 115 grains in its original .32-20 configuration.
I explained to Erik what I wanted to do, and he came up with a highly successful 82-gr. double-cavity hollow point which feeds well, mushrooming nicely from soft 8-10 BHN at .32 ACP velocity, also providing a “fragmenting varmint bomb” with harder 11-15 BHN alloy when fired from the 7.62x25.
He did this by machining the mold blocks to remove the original base band and bottom lube groove. He then cut a new front driving band .11 wide and .311 diameter ahead of the remaining lube groove to restore some needed bearing surface, shortening the nose somewhat. The HP cavity resembles the form of the Speer 65 gr. Gold Dot for the .32 ACP and using his inset bar conversion, production is as good or better than when casting with the original unmodified double-cavity mold. Bullet shape resembles flat nosed hardball and it feeds in all my pistols like a pony trotting.
Casting the new 82-grain #3118 HP from wheel weights + 2% tin alloy, driving it at 1330 f.p.s. using 5 grains of Bullseye in the 7.62x25, functioning is sluggish, but reliable, dropping empty brass at your feet. Water jug tests were impressive, blowing the first gallon jug to smithereens in a manner similar to 110-grain .357 Magnum loads. The front third of the bullet fragments violently, showering the second and third jugs with multiple secondary projectiles about the size of No.6 birdshot. The base of the bullet flattens to 8mm diameter, weighs 65 grains, like a .32 ACP slug, penetrating into, but stopping in the fourth jug, denting its far side, not exiting. The resulting 30 inches of water penetration for the fragmented stub equates to 18+ inches of water. Adequate penetration for a defense load.
I would have no issues keeping the CZ52 around as a spare defensive pistol. Not fancy, BUT IT WORKS. Now if I cast these out of junk silver, what would they weigh and would they work on vampires?