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Clark · June 5, 2007, 10:44 PM

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

==========================================================
A) The "CZ52 is stronger than the Tokarev" myth in print
========================================================
1970:
From the U. S. Army Foreign Science and Technology Center's publication
titled "Small Arms Identification and Operation Guide - Eurasian
Communist Countries", (FSTC-CW-07-03-70), page 211, Table XI, Cartridge
Data and Color Codes, in reference to 7.62 x 25 mm pistol ball type P;
"Do not use Czechoslovak-made ammunition in TT-33 pistols."

1996
rec.guns FAQ by James Bardwell ([email protected])2/18/96
" The CZ-52 uses a 8 round single stack mag. It utilizes a roller
locking system to safely use all sorts of Tok ammo, from less powerful
loads for the Tokarev pistol, to very powerful loads meant for this
handgun (Czech M48 round) and also for PPSh submachine guns."
http://www.recguns.com/Sources/IIIC2f.html

1995
"Sierra 50th Anniversary Edition Handgun Reloading Manual"
"..the Vz24 is an extremely strong pistol. Reload developed for pistols
using less robust locking systems must be reduced drastically for safety
reasons. In recoil operate pistols, such as the Tokarev, starting loads
shown should considered maximum,"

1995:
From the American Rifleman magazine, August 1995, page 44;
"The Czech version of the 7.62 x 25 mm cartridge is based on the Soviet
7.62 mm Type P pistol cartridge used in the TT-30 and TT-33 Tokarev, but
Czech ammunition is loaded considerably heavier that its Soviet
counterpart. While dimensionally similar to the 7.63 Mauser cartridge,
inter changeability is not recommended as the commercially loaded Mauser
ammunition is considered too light to reliably cycle the Model 52."

When I wrote Sierra in 2003 about this, they wrote back:

Rich wrote:

" Clark,
Thanks for the information.
We would be interested in some details if you have time to share
them. Obviously Kevin (the author) was referring to the locking
mechanisms and not the barrels but we certainly are interested in your
findings. They may save someone the experience you have had with these
guns.
Rich" [Machholz]

2000
Ted Curtis ballistician at Accurate Arms in March of 2000:
"7.62 X 25 Tokarev ..
Due to the large number of handguns imported into the U.S. chambered
for the 7-62 x 25 Tokarev Accurate Arms has developed the following load
data for those shooters who wish to reload the little powerhouse. In
determining the appropriate pressure limit for our load data we tested
various military ammo from China, Russia, Austria Bulgaria and the
Czech Republic. Commercial ammo produced by Sellier & Bellot was also
tested. Based on these tests we arrived at a maximum pressure for our
lad data of 42,000 C.U.P. Only the single lot of Russian ammo was
significantly below this pressure averaging 31,000 C.U.P. The consistent
pressures between all other type sand manufactures was a welcome
surprise . Indeed, the fact that CZech ammo, made for the CZ-52 pistol,
produced the same pressure as that of the other countries was perhaps
the biggest surprise of the whole project. This in spite of the "tribal
lore" regarding this particular handgun and the ammo loaded for it
claiming that shooting Czech ammo in any other firearm so chambered will
causes spontaneous disassembly. The pressure data produced by the ammo
tested certainly doesn't support this theory."

AA has not returned my emails on the subject of me blowing up CZ52s with
their loads and powder.

2000:
"Hornady Handbook of Cartridge Reloading Fifth Edition" 2000
"Automatic pistols for the 7.62mm Tokarev were essentially knock-offs of
the Browning-designed 45 Automatic Colt Pistol, though both imitation
and some original design contribute to the Soviet auto. Our CZ-52
pistol, one of many recent imports, was both strong and well made."

2003"
Gun World" May 2003, Jan Libourel writes, "Pressures with this
cartridge [7.62x25mm] tend to run high, especially with some of the very
hot Czech loads designed for the sturdy vz52."

When I wrote him, Jan wrote back:
"Thanks for the info. I have never done any shooting to speak with the
7.62x25, so I was just passing on the "conventional gunwriter wisdom" on
these matters. This is not necessarily the truth, as you point out. Thanks
for the info.
Cordially,
Jan Libourel"

2007
Shotgun News Jan 1, 2007 "Tula Tokarev" by Peter G. Kokalis
"Czech M48 7.62x25mm ammunition should be avoided in Tokarev-type
pistols, as it was design for submachine guns and the very strong,
roller-locked vz52 pistol."

Shotgun News has not returned my emails on this subject.

=========================================================================
B) The questioning of the "CZ52 is stronger than the Tokarev" myth on
the internet
=========================================================================
2000
1) I blew up 2 CZ52 pistols that split the barrels and took pictures.
http://www.thehighroad.org/attachmen...7&d=1059258212
2) Ken Marsh, long time rec.guns contributor, pointed out that the crack
propagation seemed to start from a think spot in the chamber chamber
where there was undercutting for space for the roller blocks.

2003
1) Jaque Clarke "Uncle Jaque", a CZ52 owner, makes a drawing of this
thin spot. Here is the drawing:
http://www.thehighroad.org/attachmen...47360&d=116269...
2) I am unable to blow up any of my Tokarev pistols, with what blows up
CZ52s and much more.
3) I buy a broom handle 1896 Mauser 30 Mauser to compare to CZ52
strength. It blows primers, but does not blow up at the loads that blow
up CZ52s. I cannot go higher with these primers.

2005:
1) John Becrovitz, long time rec.guns contributor, buys 10 CZ52 barrels
and tests them for hardness. Measurements between RC25 and RC35 were
taken on intact 7.62x25mm barrels. A more modern 9mm CZ52 barrel tests
at RC47.

2) Accurate Arms "revised" their hot loads for the CZ52 only. This
example is for 110 gr SPR RN 1.3":
a) The hot load from 2000: 11.7 gr AA#9 41,800 c.u.p 1688 fps
b) The wimpy load from 2005 8.5 gr AA#9, 34270 psi, 1248 fps

http://www.accuratepowder.com
click on "30 (7.62)"
click on "7.62x25 Tokarev"

"Lynn,
As a result of various technical reasons, the data in the initial print
(year 2000) of the no 2 guide were not tested against a verifiable
standard or protocol.
As a result wrong conclusions and assumptions were made. The result was
that the initial loads were too high.
The recent adjustments were made in two phase’s i.e.
a) A Reduction in velocity to conform to the correct barrel length since
the initial velocities was for a 9” test barrel.
b) The adjustment of the actual charge weights to conform to the only
Specification/protocol in existence i.e. CIP “Commission International
Permanente” which is the authority, since this caliber does come from
Europe.
This pressure limit is : <2400bar or 34809Psi.
The final loads as published on the website are thus inline with these
standards.
However, due to the strong design of the CZ 52 pistol, people have been
using ex submachine gun(i.e. PPsh-41) ammunition from the eastern bloc,
which obviously were loaded to a much higher levels, and some of these
will function in the CZ 52 pistol. However, there is ammunition that
will even destroy the CZ 52.
Although the CZ52 gun can handle much higher pressures than some other
weapons it has never been incorporated into an official specification.
The strength of this gun is renowned, which lead to many “estimations”
of performance and a reputation of being able to handle just about
anything out there on the market.
This is obviously not true and we deemed it necessary to conform to the
official International specifications for the cartridge.

Regards
Johan Loubser
Ballistic Lab manager
Accurate Powders"

What does it all mean?
I have never got any published source to recant in print the myth about CZ52 strength, but the current published loads for CZ52s, Tokarevs, and broomhandles is now below that of original factory ammo for CZ52s, Tokarevs, or broomhandles. The loads are now lower than the lowest common denominator. Admit no errors, but lower the loads was the reaction.

June 5, 2007, 10:44 PM	#7
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 4,678	CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information. ========================================================== A) The "CZ52 is stronger than the Tokarev" myth in print ======================================================== 1970: From the U. S. Army Foreign Science and Technology Center's publication titled "Small Arms Identification and Operation Guide - Eurasian Communist Countries", (FSTC-CW-07-03-70), page 211, Table XI, Cartridge Data and Color Codes, in reference to 7.62 x 25 mm pistol ball type P; "Do not use Czechoslovak-made ammunition in TT-33 pistols." 1996 rec.guns FAQ by James Bardwell ([email protected])2/18/96 " The CZ-52 uses a 8 round single stack mag. It utilizes a roller locking system to safely use all sorts of Tok ammo, from less powerful loads for the Tokarev pistol, to very powerful loads meant for this handgun (Czech M48 round) and also for PPSh submachine guns." http://www.recguns.com/Sources/IIIC2f.html 1995 "Sierra 50th Anniversary Edition Handgun Reloading Manual" "..the Vz24 is an extremely strong pistol. Reload developed for pistols using less robust locking systems must be reduced drastically for safety reasons. In recoil operate pistols, such as the Tokarev, starting loads shown should considered maximum," 1995: From the American Rifleman magazine, August 1995, page 44; "The Czech version of the 7.62 x 25 mm cartridge is based on the Soviet 7.62 mm Type P pistol cartridge used in the TT-30 and TT-33 Tokarev, but Czech ammunition is loaded considerably heavier that its Soviet counterpart. While dimensionally similar to the 7.63 Mauser cartridge, inter changeability is not recommended as the commercially loaded Mauser ammunition is considered too light to reliably cycle the Model 52." When I wrote Sierra in 2003 about this, they wrote back: Rich wrote: " Clark, Thanks for the information. We would be interested in some details if you have time to share them. Obviously Kevin (the author) was referring to the locking mechanisms and not the barrels but we certainly are interested in your findings. They may save someone the experience you have had with these guns. Rich" [Machholz] 2000 Ted Curtis ballistician at Accurate Arms in March of 2000: "7.62 X 25 Tokarev .. Due to the large number of handguns imported into the U.S. chambered for the 7-62 x 25 Tokarev Accurate Arms has developed the following load data for those shooters who wish to reload the little powerhouse. In determining the appropriate pressure limit for our load data we tested various military ammo from China, Russia, Austria Bulgaria and the Czech Republic. Commercial ammo produced by Sellier & Bellot was also tested. Based on these tests we arrived at a maximum pressure for our lad data of 42,000 C.U.P. Only the single lot of Russian ammo was significantly below this pressure averaging 31,000 C.U.P. The consistent pressures between all other type sand manufactures was a welcome surprise . Indeed, the fact that CZech ammo, made for the CZ-52 pistol, produced the same pressure as that of the other countries was perhaps the biggest surprise of the whole project. This in spite of the "tribal lore" regarding this particular handgun and the ammo loaded for it claiming that shooting Czech ammo in any other firearm so chambered will causes spontaneous disassembly. The pressure data produced by the ammo tested certainly doesn't support this theory." AA has not returned my emails on the subject of me blowing up CZ52s with their loads and powder. 2000: "Hornady Handbook of Cartridge Reloading Fifth Edition" 2000 "Automatic pistols for the 7.62mm Tokarev were essentially knock-offs of the Browning-designed 45 Automatic Colt Pistol, though both imitation and some original design contribute to the Soviet auto. Our CZ-52 pistol, one of many recent imports, was both strong and well made." 2003" Gun World" May 2003, Jan Libourel writes, "Pressures with this cartridge [7.62x25mm] tend to run high, especially with some of the very hot Czech loads designed for the sturdy vz52." When I wrote him, Jan wrote back: "Thanks for the info. I have never done any shooting to speak with the 7.62x25, so I was just passing on the "conventional gunwriter wisdom" on these matters. This is not necessarily the truth, as you point out. Thanks for the info. Cordially, Jan Libourel" 2007 Shotgun News Jan 1, 2007 "Tula Tokarev" by Peter G. Kokalis "Czech M48 7.62x25mm ammunition should be avoided in Tokarev-type pistols, as it was design for submachine guns and the very strong, roller-locked vz52 pistol." Shotgun News has not returned my emails on this subject. ========================================================================= B) The questioning of the "CZ52 is stronger than the Tokarev" myth on the internet ========================================================================= 2000 1) I blew up 2 CZ52 pistols that split the barrels and took pictures. http://www.thehighroad.org/attachmen...7&d=1059258212 2) Ken Marsh, long time rec.guns contributor, pointed out that the crack propagation seemed to start from a think spot in the chamber chamber where there was undercutting for space for the roller blocks. 2003 1) Jaque Clarke "Uncle Jaque", a CZ52 owner, makes a drawing of this thin spot. Here is the drawing: http://www.thehighroad.org/attachmen...47360&d=116269... 2) I am unable to blow up any of my Tokarev pistols, with what blows up CZ52s and much more. 3) I buy a broom handle 1896 Mauser 30 Mauser to compare to CZ52 strength. It blows primers, but does not blow up at the loads that blow up CZ52s. I cannot go higher with these primers. 2005: 1) John Becrovitz, long time rec.guns contributor, buys 10 CZ52 barrels and tests them for hardness. Measurements between RC25 and RC35 were taken on intact 7.62x25mm barrels. A more modern 9mm CZ52 barrel tests at RC47. 2) Accurate Arms "revised" their hot loads for the CZ52 only. This example is for 110 gr SPR RN 1.3": a) The hot load from 2000: 11.7 gr AA#9 41,800 c.u.p 1688 fps b) The wimpy load from 2005 8.5 gr AA#9, 34270 psi, 1248 fps http://www.accuratepowder.com click on "30 (7.62)" click on "7.62x25 Tokarev" "Lynn, As a result of various technical reasons, the data in the initial print (year 2000) of the no 2 guide were not tested against a verifiable standard or protocol. As a result wrong conclusions and assumptions were made. The result was that the initial loads were too high. The recent adjustments were made in two phase’s i.e. a) A Reduction in velocity to conform to the correct barrel length since the initial velocities was for a 9” test barrel. b) The adjustment of the actual charge weights to conform to the only Specification/protocol in existence i.e. CIP “Commission International Permanente” which is the authority, since this caliber does come from Europe. This pressure limit is : <2400bar or 34809Psi. The final loads as published on the website are thus inline with these standards. However, due to the strong design of the CZ 52 pistol, people have been using ex submachine gun(i.e. PPsh-41) ammunition from the eastern bloc, which obviously were loaded to a much higher levels, and some of these will function in the CZ 52 pistol. However, there is ammunition that will even destroy the CZ 52. Although the CZ52 gun can handle much higher pressures than some other weapons it has never been incorporated into an official specification. The strength of this gun is renowned, which lead to many “estimations” of performance and a reputation of being able to handle just about anything out there on the market. This is obviously not true and we deemed it necessary to conform to the official International specifications for the cartridge. Regards Johan Loubser Ballistic Lab manager Accurate Powders" What does it all mean? I have never got any published source to recant in print the myth about CZ52 strength, but the current published loads for CZ52s, Tokarevs, and broomhandles is now below that of original factory ammo for CZ52s, Tokarevs, or broomhandles. The loads are now lower than the lowest common denominator. Admit no errors, but lower the loads was the reaction.