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7.5×54mm French

7.5×54mm MAS mod. 1929
7.5x54mmMAS.jpg
Type Rifle
Place of origin  France
Service history
In service 1929–1990
Used by France, Germany, Vietnam
Wars World War II
First Indochina War
Algerian War
Suez Crisis
Vietnam War
Shaba II
Production history
Designer MAS
Designed 1924
Variants Balle "C", Balle "D"
Specifications
Parent case 7.5×57mm MAS mod. 1924
Case type Rimless, bottleneck
Bullet diameter 7.84 mm (0.309 in)
Neck diameter 8.66 mm (0.341 in)
Shoulder diameter 11.30 mm (0.445 in)
Base diameter 12.25 mm (0.482 in)
Rim diameter 12.34 mm (0.486 in)
Rim thickness 1.40 mm (0.055 in)
Case length 54.00 mm (2.126 in)
Overall length 76.00 mm (2.992 in)
Case capacity 3.76 cm3 (58.0 gr H2O)
Rifling twist 270 mm (10.63 inches)
Primer type Berdan or Boxer Large rifle
Maximum pressure (C.I.P.) 380.00 MPa (55,114 psi)
Ballistic performance
Bullet mass/type Velocity Energy
9.0 g (139 gr) Balle C FMJ 820 m/s (2,700 ft/s) 3,026 J (2,232 ft·lbf)
9.0 g (139 gr) FMJ Privi Partizan 830 m/s (2,700 ft/s) 3,104 J (2,289 ft·lbf)
9.0 g (139 gr) SP 850 m/s (2,800 ft/s) 3,550 J (2,620 ft·lbf)
11.7 g (181 gr) SP 790 m/s (2,600 ft/s) 3,650 J (2,690 ft·lbf)
12.35 g (191 gr) Balle D FMJ 694 m/s (2,280 ft/s) 2,974 J (2,194 ft·lbf)
Test barrel length: 574 mm (22.60 in) and
600 mm (23.62 in)

Source(s): C.I.P. SurplusRifle.com /Cartridges of the World

The 7.5×54mm French or 7.5 French (designated as the 7,5 × 54 MAS by the C.I.P.) is a rimless bottlenecked rifle cartridge. It was developed by France as an update to the 7.5×57mm MAS mod. 1924 cartridge. It replaced the obsolete 8×50mmR Lebel round used during World War I.

The 7.5×54mm French chamber has an uncommon 12.39 mm (0.488 in) breech diameter and is ballistically comparable to the 7.62×51mm NATO/.308 Winchester round. The 7.5 French cartridge is somewhat similar in appearance to the slightly longer and thicker 7.5×55mm Swiss GP11 round but users should never try to interchange the two rounds.

By the end of World War I the French Army realized that it needed to update its once revolutionary, but now obsolete, 8 mm Lebel ammunition. Due to the demands of mass production of the 8mm Lebel round during World War I it was not able to do so until the war had ended in November 1918. Six years later, the 7.5×57mm MAS cartridge was introduced in 1924. However it was soon replaced in 1929 with the slightly shorter 7.5×54mm MAS 1924-M29 . Two bullet variations were tested for military use at the time, the 1924 C and 1924 D, the former being lighter than Balle 1924 D.

The French Army chose to adopt "light ball" 9.0 grams (139 gr) Balle C flat base spitzer bullet ammunition for universal service in the MAS-36 and MAS-49 rifles as well as in the Mle 1924-29 machine rifle. The "heavy ball" 12.35 grams (190.6 gr) Balle 1929 D featured a boat-tailed spitzer bullet and had limited specialized use in automatic weapons like the Mle 1931 F and the FM Mle 1924M29 machine guns.


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