7.65×20mm Long

The 7.65×20mm Long was designed at Remington Arms in 1917 by John Pedersen as a compact, rimless pistol-and-carbine round intended for the semi-automatic Pedersen device, an insert that let a bolt-action Springfield rifle fire it as a semi-automatic carbine. The device never reached combat before the First World War ended, but France adopted the cartridge afterward for its own service pistols and submachine guns, and it remained in French service use into the 1960s under the name 7.65mm Longue.

Its straight, rimless case and small overall length reflect its origin as a compact intermediate round rather than a full-power rifle cartridge: it was built to give a pistol- or carbine-length action worthwhile range and accuracy without the size or recoil of a full rifle round, sitting between contemporary pistol cartridges and full-power rifle rounds of the period. France chambered it in service pistols such as the MAS Modèle 1935 series and in submachine guns including the MAS-38.

This entry’s dimensions come from Wikipedia’s infobox, none of them individually cited on Wikipedia itself, and no free C.I.P. or SAAMI dimensional standard was found for this military round — it never went into commercial production outside France’s own service channels. The one ballistics figure Wikipedia’s infobox publishes, a 77-grain full metal jacket bullet, states no test-barrel length, so it is recorded here as a bullet weight only, with no velocity point.