Also note the difference between the standard 30calibre and the M1 Carbine cartridge (this is not live by the way! I remade it from a spent cartridge case and bullet found separately). Take particular note of the difference between a standard 30calibre American cartridge and the British 303. To start with, here are the main allied small arms cartridges lined up so you can see the difference in overall shape and size. You may find it easier to watch a video on this subject instead, so here is one I made a few months back. Armour Piercing (AP), Incendiary (I), Armour Piercing Incendiary (API), Tracer (T)), ‘mark’ of cartridge and even the type of alloy used to make the cartridge case. Belted cartridge cases have a thicker ‘belt’ positioned just above the extraction groove, and rebated cases have a rim that is smaller in diameter than the cartridge case.Īs for the headstamps themselves, (the markings on the head of the cartridge case), these can give all sorts of information about calibre, manufacturer, year of manufacture, cartridge fill, cartridge type, (e.g.
Semi-rimmed cartridge cases have an extraction groove and a rim very slightly larger than the diameter of the cartridge case. With a rimless cartridge case, the rim is exactly the same diameter as the cartridge case, which starts above the extraction groove. However, it really isn’t! A rimmed cartridge is called that because the very bottom portion of the head, the ‘rim’, is wider than the main body of the cartridge. This terminology looks, at first glance, to be a little complicated. This can also help ID certain bullets.Īpart from the headstamp itself, (the marking on the base of a cartridge case), the rim is perhaps the most important. A cartridge case should never be called a bullet! It is simply NOT correct! The bullet itself has a core and a jacket, along with a groove called a cannelure.
20mm Oerlikon has a much longer more graduated shoulder than 20mm Hispano-Suiza).Īs this second diagram shows, the bullet is the projectile that leaves the weapon at high speed when the cartridge is fired. The neck can give an approximate calibre, (although the diameter inside the mouth is more accurate), and the slope of the shoulder can differentiate between similar cartridge cases (e.g. All of these can give vital clues to identifying a cartridge case. The most important of these are the neck, shoulder, rim and head. A basic knowledge of terminology will help a collector identify the calibre, origins and use of a cartridge case.Īs you can see from the above diagram, there are a number of terms that collectors use when referring to cartridge cases.
Identification of cartridge cases is important for any collector of WW2 ordnance.