8×50mmR Mannlicher

Note: Not to be confused with the French 8×50R Lebel cartridge.

The Austro-Hungarian 8×50mmR Mannlicher or 8×50mmR M93 is an old cartridge dating back to the days of black powder.

M88
The 8×50mmR Mannlicher cartridge was first introduced in 1888 for the Mannlicher Repetier-Gewehr M.88, an updated version of the Mannlicher M.86. The M.88 (and later M.88/90 and M.90) used a slightly updated version of the "wedge-lock" bolt system that the earlier M.86 rifle used. Many M.86 rifles were converted to the new cartridge, creating the M.86/88 and M.86/90. In its initial incarnation, the round was given the designation 8 mm M.1888 scharfe Patrone. It was loaded with a 244gr round nosed bullet and a 62gr charge of compressed black powder. This gave the bullet an approximate velocity of 1750 ft/s out of the M.88's 30" barrel.

M90
In approximately 1890 the Austro-Hungarian empire converted the round into a semi-smokeless cartridge, following upon the heels of France's 8 mm Lebel cartridge, the first smokeless military round. This new round was designated 8 mm M.1890 scharfe Patrone or "Nitro-Patrone". It was loaded with the same 244gr bullet but carried a 43gr charge of "Gewehrpulver" ("rifle powder", Austria-Hungary's name for their version of smokeless powder, which was actually a "semi-smokeless" powder). The new semi-smokeless loading pushed the bullet to a velocity of 1950 ft/s in the converted M.88/90 and M.86/90 Mannlicher rifles.

M93
In 1893 the loading was once again updated with the perfection of a completely smokeless powder by the Austro-Hungarians. This new loading was designated 8 mm M.1893 scharfe Patrone, it was loaded with the same bullet as the two previous loadings but used a 43gr charge of the new Gewehrepulver M.1892. This improved ballistics slightly to 2035 ft/s out of the long M.88/90 and later M.95 long rifles, it was about 200 ft/s less out of the Repetier-Carabiner M.90 and M.95. It was later replaced by (and many weapons rechambered for) the 8x56mmR cartridge.

Current Use
The IOF.315 Sporting Rifle uses this cartridge under the title of .315 as discussed here http://indiansforguns.com/viewtopic.php?f=13&t=760&start=240#p39378

The 8x50mmR Mannlicher cartridge has a long history of sporting use in India, as it was a simple matter to modify the Lee-Enfield action to accommodate the 8x50mmR in place of the .303 inch cartridge, thus providing a solution to the British colonial administration's ban on civilians possessing rifles chambering British military cartridges while offering a cartridge of similar capabilities.

British gunmakers BSA produced sporting versions of the Lee-Enfield military rifle, chambered in "8mm (.315")" from well before World War I until at least the 1930s. The British-founded "Rifle Factory Ishapore" continues to manufacture Lee-Enfield sporting rifles in this chambering.

Handloading
Reloadable cartridge cases can be produced by reforming and trimming 8×56mmR Mannlicher or 7.62×54mmR Mosin-Nagant Russian brass. Standard .323" 8mm S-bullets are correct for this caliber though best results will be obtained from open-base bullets that can expand to fit the .329" bore. RCBS offers both reforming and reloading matrices.

If reloading for "wedge-lock" Mannlicher rifles such as the M.88, M.86/88, M.86/90 or M.88/90 then chamber pressures should be kept low for safety. Rifles such as the Mannlicher M.95 using a stronger rotating-bolt design can be loaded to higher pressures.