.310 Cadet Rifle Load Data

The .310 Cadet cartridge, also known as the .310 Greener, has its origins in the late 19th and early 20th centuries in the United Kingdom and Australia. It was developed specifically as a training round for military cadets and was most famously chambered in the Martini Cadet rifle, a single-shot falling-block rifle manufactured primarily by the Birmingham Small Arms Company (BSA). The cartridge itself was based on the .297/250 Rook, a small game and target round popular in the UK, but modified with a slightly increased bullet diameter and case length to suit the needs of cadet training. Production of both rifles and ammunition was extensive from the late 1890s through the 1920s, and surplus Martini Cadet rifles were widely distributed and used for civilian marksmanship and sporting purposes in Australia.

In terms of application, the .310 Cadet began as a military training round but found a lasting place among civilian shooters for target practice and small game hunting. Due to its mild recoil and manageable report, the cartridge has been a favorite for beginners, youths, and recreational shooters. The Martini Cadet rifles chambered for this cartridge are still sought after by collectors and enthusiasts for their historical value and robust build. While not considered powerful by modern standards, the .310 Cadet is accurate and enjoyable for plinking at the range or dispatching small vermin. Its gentle shooting characteristics have also made it popular for club competitions and informal target shooting in rural areas, where its external ballistics are more than sufficient at closer ranges.

The .310 Cadet cartridge, given its modest ballistics, is used primarily for taking small game such as rabbits, hares, and possums. Some rural shooters in Australia have utilized it for foxes at short to moderate ranges, but the caliber is generally better suited for lighter-bodied species due to its relatively low energy and velocity. The traditional lead projectile design offers good stopping power on small targets without excessive meat damage, which is important for hunters who harvest game for the table. In addition, the cartridge’s mild report and recoil make it ideal for discreet pest control around farms and outbuildings, where noise can be an issue.

Bullet weights for the .310 Cadet are quite standardized, with the most common projectile being a heeled lead bullet weighing approximately 120 grains and measuring about .323 inches in diameter, despite the "310" designation. This heeled design, similar to the .22 Long Rifle, was intended for consistent chamber sealing and accuracy from the Martini Cadet’s shallow-rifled barrel. Typical muzzle velocities for factory ammunition were in the range of 1,200 to 1,400 fps, translating to modest energy suitable for small game. The cartridge features a rimmed, bottlenecked case that is easy to handle and reload. One of the unique characteristics of this caliber for reloaders is the challenge in sourcing proper heeled bullets and reloading dies, as modern production has largely ceased and the rifles have non-standard dimensional tolerances. Nonetheless, the .310 Cadet remains popular among enthusiasts as a nostalgic and practical cartridge, especially among those who appreciate traditional riflecraft and the satisfaction of working with vintage arms.