7.5×57mm MAS
The 7.5×57mm MAS or 7.5×58mm mle 1924c was a short-lived French rifle cartridge that was introduced in the mid-1920s to replace the 8×50mmR Lebel, although it itself was soon replaced with the 7.5×54mm French round, that served the French for decades to come until France, along with the rest of NATO, adopted the standard NATO calibers, 5.56×45mm NATO and 7.62×51mm NATO.
| 7.5 mm MAS | |
|---|---|
| Type | Rifle |
| Place of origin | France |
| Service history | |
| Used by | France |
| Production history | |
| Produced | 1924 to 1929 |
| Specifications | |
| Parent case | 6.5×55mm |
| Case type | Rimless, bottleneck |
| Bullet diameter | 7.8 mm (0.31 in) |
| Neck diameter | 8.6 mm (0.34 in) |
| Shoulder diameter | 11.2 mm (0.44 in) |
| Base diameter | 12.2 mm (0.48 in) |
| Rim diameter | 12.2 mm (0.48 in) |
| Rim thickness | 1.4 mm (0.055 in) |
| Case length | 57.6 mm (2.27 in) |
Description
The obsolete 8mm Lebel round was powerful and accurate but due to its shape it was particularly poorly suited to automatic weapons with large-capacity magazines.[1] The only weapon ever fielded in 7.5 mm MAS mod. 1924 was the fusil-mitrailleur mle 1924, a light machinegun based on the B.A.R action. Early examples of the FM 24 proved prone to various failures; additionally, it was possible to mistake the new 7.5×57mm for a German 7.92×57mm Mauser round. The Mauser round would chamber and fire, but the larger bullet would not fit in the barrel and could cause a catastrophic malfunction. The new 7.5 mm round was abandoned and replaced by the 7.5×54mm MAS mod. 1929.[2]
References
- "7.5x54mm MAS".
- Ferrard, Stéphane (1998). France 1940 l'armement terrestre. ETAI. ISBN 2-7268-8380-X.