The .303 British is one of the few (along with the .22 Hornet, .30-30 Winchester, and 7.62×54mmR) bottlenecked, rimmed centerfire rifle cartridges still in common use today.
Most of the bottleneck rimmed cartridges of the late 1880s and 1890s fell into disuse by the end of the First World War.

Commercial ammunition for weapons chambered in .303 British is readily available, as the cartridge is still manufactured by major producers such as Remington, Federal, Winchester, Sellier & Bellot, Denel-PMP, Prvi Partizan and Wolf.
Commercially produced ammunition is widely available in various full metal jacket bullet, soft point, hollow point, flat-based and boat tail designs—both spitzer and round-nosed.

Reloading equipment and ammunition components are also manufactured by several companies.
Dies and other tools for the reloading of .303 British are produced by Forster, Hornady, Lee, Lyman, RCBS, and Redding.
Depending on the bore and bore erosion a reloader may choose to utilize bullet diameters of .308–.312" with .311" or .312" diameter bullets being the most common.
Bullets specifically produced and sold for reloading .303 British are made by Sierra, Hornady, Speer, Woodleigh, Barnes, and Remington.
Where extreme accuracy is required, the Sierra Matchking 174-grain (11.3 g) HPBT bullet is a popular choice.
Sierra does not advocate use of Matchking brand bullets for hunting applications.
For hunting applications, Sierra produces the ProHunter in .311" diameter.
The increasingly popular all-copper Barnes TSX is now available in the .311" diameter as a 150 gr projectile which is recommended by Barnes for hunting applications.

With most rifles chambered in .303 British being of military origin, success in reloading the calibre depends on the reloader's ability to compensate for the often loose chamber of the rifle.
Reduced charge loads and neck sizing are two unanimous recommendations from experienced loaders of .303 British to newcomers to the calibre.
The classic 174-grain (11.3 g) FMJ bullets are widely available, though purchasers may wish to check whether or not these feature the tail-heavy Mk 7 design.
In any case other bullet weights are available, e.g. 150, 160, 170, 180, and 200-grain (13 g), both for hunting and target purposes.
The .303 British is one of the few (along with the .22 Hornet, .30-30 Winchester, and 7.62×54mmR) bottlenecked, rimmed centerfire rifle cartridges still in common use today. Most of the bottleneck rimmed cartridges of the late 1880s and 1890s fell into disuse by the end of the First World War.
Commercial ammunition for weapons chambered in .303 British is readily available, as the cartridge is still manufactured by major producers such as Remington, Federal, Winchester, Sellier & Bellot, Denel-PMP, Prvi Partizan and Wolf. Commercially produced ammunition is widely available in various full metal jacket bullet, soft point, hollow point, flat-based and boat tail designs—both spitzer and round-nosed.
Reloading equipment and ammunition components are also manufactured by several companies. Dies and other tools for the reloading of .303 British are produced by Forster, Hornady, Lee, Lyman, RCBS, and Redding. Depending on the bore and bore erosion a reloader may choose to utilize bullet diameters of .308–.312" with .311" or .312" diameter bullets being the most common. Bullets specifically produced and sold for reloading .303 British are made by Sierra, Hornady, Speer, Woodleigh, Barnes, and Remington. Where extreme accuracy is required, the Sierra Matchking 174-grain (11.3 g) HPBT bullet is a popular choice. Sierra does not advocate use of Matchking brand bullets for hunting applications. For hunting applications, Sierra produces the ProHunter in .311" diameter. The increasingly popular all-copper Barnes TSX is now available in the .311" diameter as a 150 gr projectile which is recommended by Barnes for hunting applications.
With most rifles chambered in .303 British being of military origin, success in reloading the calibre depends on the reloader's ability to compensate for the often loose chamber of the rifle. Reduced charge loads and neck sizing are two unanimous recommendations from experienced loaders of .303 British to newcomers to the calibre. The classic 174-grain (11.3 g) FMJ bullets are widely available, though purchasers may wish to check whether or not these feature the tail-heavy Mk 7 design. In any case other bullet weights are available, e.g. 150, 160, 170, 180, and 200-grain (13 g), both for hunting and target purposes.
.303 British