.310 Cadet (Martini)

.310 Cadet (Martini)

The .310 Cadet cartridge, also known as the .310 Greener or .310 Martini, was developed in the late 19th century for use in the Martini Cadet single-shot rifles, which were issued to Australian military cadets. Originally a black powder cartridge, it later transitioned to smokeless powder use. The cartridge uses a heeled lead bullet, most commonly weighing 120 grains, and is designed for relatively low pressures, making it ideal for training and marksmanship practice.

Typical factory loads propelled a 120-grain lead bullet at around 1,200 feet per second, offering mild recoil and sufficient accuracy for target shooting and small game hunting. Reloading the .310 Cadet can be challenging due to its heeled bullet design, which requires special attention to bullet fit and case preparation. Shooters often cast their own bullets or purchase custom options to maintain performance and authenticity.

The cartridge's popularity declined in the mid-20th century as military surplus rifles became less common and .22 LR became the standard for cadet and small-bore training rifles. However, the .310 Cadet remains popular among collectors and enthusiasts who appreciate its historical value and enjoy shooting vintage Martini Cadet rifles.

Note: Reloading components for the .310 Cadet can be difficult to find, and reloading practices often involve modified or hand-cast bullets to fit the heeled design properly. Always consult reliable sources for safe load data.

Source: Wolfe Publishing – Handloader #137 (January 1989)