8×50mmR Lebel

8×50mmR (8 mm Lebel/Balle D)
Type Rifle
Place of origin France, French Third Republic
Service history
In service 1886–1944
Used by See Users
Wars French colonial campaigns,
World War I,
World War II,
and other conflicts
Production history
Variants Balle M, balle D, balle N, balle T, balle P
Specifications
Parent case 11×59mmR Gras
Case type Rimmed, bottlenecked
Bullet diameter 8.30 mm (0.327 in)
Neck diameter 8.85 mm (0.348 in)
Shoulder diameter 11.42 mm (0.450 in)
Base diameter 13.77 mm (0.542 in)
Rim diameter 16.00 mm (0.630 in)
Rim thickness 1.40 mm (0.055 in)
Case length 50.50 mm (1.988 in)
Overall length 75.00 mm (2.953 in)
Rifling twist 240 mm (1 in 9.45 inch)
Primer type Large rifle
Maximum pressure 320.00 MPa (46,412 psi)
Ballistic performance
Bullet mass/type Velocity Energy
12.8 g (198 gr) Balle D FMJ 730 m/s (2,400 ft/s) 3,364 J (2,481 ft⋅lbf)
15 g (231 gr) Balle N FMJ 690 m/s (2,300 ft/s) 3,751 J (2,767 ft⋅lbf)
Source(s): C.I.P.[1][2]

The 8×50mmR Lebel (8mm Lebel) (designated as the 8 × 51 R Lebel by the C.I.P.[1]) rifle cartridge was the first smokeless powder cartridge to be made and adopted by any country. It was introduced by France in 1886. Formed by necking down the 11×59mmR Gras black powder cartridge, the smokeless 8mm Lebel cartridge started a revolution in military rifle ammunition. Standard 8mm Lebel military ammunition was also the first rifle ammunition to feature a spitzer boat tail bullet (balle D), which was adopted in 1898.[3] The long-range ballistic performance of the 8mm Lebel bullet itself was exceptional for its time. For use in the magazine tube-fed early Lebel rifle, the 8 mm case was designed to protect against accidental percussion inside the tube magazine by a circular groove around the primer cup which caught the tip of the following pointed bullet. However, the shape of its rimmed bottle-necked case, having been designed for the Lebel rifle's tube magazine, also precluded truly efficient vertical stacking inside a vertical magazine. The bolt thrust of the 8mm Lebel is relatively high compared to many other service rounds used in the early 20th century. Although it was once revolutionary, the 8mm Lebel was declared obsolete after World War I and was soon after replaced with the 7.5×54mm French round.

Note

There are two commercially available 8mm Lebel cartridges: one for the Lebel Model 1886 rifle, and one for the Modèle 1892 revolver. They are two entirely different cartridges and are not interchangeable. The term "8mm Lebel" for the French Mle 1892 revolver ammunition, is only applied outside France for commercial reasons. However, the term "8mm Lebel", used to identify a rifle cartridge, is widely recognized to distinguish the French rifle cartridge from other 8 mm rifle cartridges, such as the 8×50mmR Mannlicher cartridge used by Austria-Hungary and its successor states.

8×50mmR Lebel rifle ammunition

It was originally loaded with a 15.0 g (232 grains) cupro-nickel-jacketed, lead-cored, flat-nosed, wadcutter-style bullet (balle M) which had been designed by Lieutenant Colonel Nicolas Lebel. The flat point (flat nose) of the balle M bullet had been designed to be totally safe inside the Lebel's tube magazine. It was propelled by the first practical smokeless, nitrocellulose-based, (''poudre'' B) powder as developed by Paul Vieille in 1884. The ballistic performance and range of balle M eclipsed all the previous military ammunitions in existence at the time (1886).

Technical drawings of the French 1898 pattern balle D bullet

The balle M was replaced in 1898 by a 12.8 g (198 grains) 90/10 bronze mono-metal, pointed (spitzer) boat-tail bullet called "balle D", which provided a flatter trajectory and improved long-range performance. Designed at APX (Atelier de Puteaux) by a Captain Desaleux, balle D was the first spitzer and boat-tail bullet to be placed into service by any army. Later on, in 1912, balle D ammunition was improved into balle D am ("am" stands for "amorcage modifié" or "modified primer") by crimping the primer in to prevent primer expulsions when fired in machine guns. Balle D am ammunition was in near-universal service during World War I (1914–1918) in all Lebel-caliber weapons. Balle D am ammunition was followed in 1932 by balle N ammunition, which featured a lead-cored, cupro-nickel-over-steel-jacketed, spitzer boat-tail bullet weighing 15.0 g (232 grains). It was held into a case which had a slightly larger neck diameter than the older balle D am ammunition. Balle N was heavier than balle D am and had been designed to improve the long-range performance of the Hotchkiss machine gun. Converting most Lebel-caliber rifles and carbines to the "N" ammunition was carried out during the 1930s. Balle T tracer and balle P armor-piercing rounds were also produced, along with blank and reduced charge ammunition.

In order to safely accommodate pointed (spitzer) bullets inside the Lebel's tube magazine, a circular groove was machined around each primer cup on both balle D am and balle N ammunitions. The role of that circular groove is to receive the tip of the pointed bullet that follows when loaded inside the Lebel's tube magazine. Furthermore, all Balle M and Balle D French military ammunitions feature convex primer covers which are crimped in over the primer itself. Those small convex primer covers are not noticeable, but do provide a second effective protection against accidental primer percussion inside the Lebel's tube magazine. Wartime experiences (1914–1918) involving hundreds of millions of Lebel rounds fired in combat have entirely confirmed the effectiveness of these protections.

While revolutionary for its time in terms of ballistic performance, the 8×50mmR Lebel cartridge had its drawbacks. Formed by necking down the 11mm Gras rifle cartridge case, it was an odd design, with a thick rim and a rapid double taper. This made it more difficult to feed from standard magazine firearms such as the Berthier and the Chauchat, and is the reason for the distinct curvature in the magazines of those firearms. The Lebel rifle from which it was fired was also nearly obsolete by the time balle D, let alone the balle N, came along.

Balle N ammo can only be fired from any Lebel or Berthier rifle if the chamber has beenreamed to accept the larger neck of the N cartridge. Such weapons are stamped N on top of the barrel, just in front of the receiver and behind the rear sight. Balle N ammo is identifiable by the fact that the bullet, while pointed like the solid-brass balle D, is lead-cored and jacketed with soft steel.

While newly manufactured 8×50mmR Lebel ammunition has recently become available in the U.S., reloadable cartridge cases can also be produced by reforming .348 Winchester brass. Newly manufactured Prvi Partizan 8mm Lebel ammunition is of excellent quality and replicates the performance of the original 8mm Lebel round. However, its older brass cases lack the circular groove around the primer cup, so reloaders use only round-nosed or flat-nosed bullets when producing handloads for the tube-magazine Lebel rifles with the older Privi Partizan cases. Recently manufactured Privi Partizan 8mm Lebel ammunition with spitzer bullets incorporate the circular groove in the head and are safe when stacked in the box-magazine of the Berthier rifle and the Mle 1886 tubular magazine rifle. Older Privi Partizan cases loaded with spire point bullets are fired single shot. Newer Privi Partizan cases with the circular groove follow the balle D specifications and may use the magazine for loading.

In 1929, the 7.5×54mm MAS mod. 1929 (7.5 French) cartridge was introduced. This made the 8×50mmR Lebel cartridge obsolete overnight, but due to post-World War I financial constraints and political neglect, it was not introduced as a rifle cartridge until the adoption, just before World War II, of the MAS-36 rifle.

Downrange performance comparison

1886 pattern 8×51mmR Lebel balle M load

Distance (m) 0 200 400 600 800 1,000 1,500 2,000
Trajectory (m) 0 0.14 0.81 2.39 5.27 9.83 31.71 75.61
Velocity (m/s) 628 488 397 335 290 255 197 160

1898 pattern 8×51mmR Lebel balle D load

Distance (m) 0 200 400 600 800 1,000 1,500 2,000
Trajectory (m) 0 0.12 0.54 1.43 3.01 5.60 18.30 44.0
Velocity (m/s) 700 607 521 448 388 342 278 240

Weapons using the 8mm Lebel round

Rifles

Machine guns

Users

See also

References

  1. 1 2 C.I.P. TDCC datasheet 8 × 51 R Lebel
  2. Johnson, Melvin M., Jr. (1944). Rifles and Machine Guns. New York: William Morrow & Company. p. 384.
  3. Chuck Hawks. "The 8x50R Lebel (8mm Lebel)".

Sources

  • Balle M, D, N, T, and P—By Conjay
  • Huon, Jean. Military Rifle and Machine Gun Cartridges. Alexandria, Va.: Ironside International Publishers, 1988. ISBN 0-935554-05-X.
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