The .303 British or 7.7×56mmR, is a .303-inch (7.7 mm) calibre rimmed tapered rifle cartridge. The .303 inch bore diameter is measured between rifling lands as is the common practice in Europe which follows the traditional black powder convention.
A wildcat cartridge, often shortened to wildcat, is a custom cartridge for which ammunition and/or firearms are not mass-produced. These cartridges are often created in order to optimize a certain performance characteristic of an existing commercial cartridge, or may merely be intended as novelty items.
The .270 Winchester is a rifle cartridge developed by Winchester Repeating Arms Company in 1923, and it was unveiled in 1925 as a chambering for their bolt-action Model 54 to become arguably the flattest shooting cartridge of its day, only competing with the .300 Holland & Holland Magnum, also introduced in the same year.
The term express was first applied to hunting rifles and ammunition beginning in the mid-19th century, to indicate a rifle or ammunition capable of higher than typical velocities. The early express cartridges used a heavy charge of black powder to propel a lightweight, often hollow point bullet, at high velocities to maximize point blank range. Later the express cartridges were loaded with nitrocellulose-based gunpowder, leading to the Nitro Express cartridges, the first of which was the .450 Nitro Express.
The .375 Remington Ultra Magnum, also known as the .375 RUM is a .375 rifle cartridge introduced by Remington Arms in 2000. The cartridge is intended for large and dangerous game.
The 7mm-08 Remington is a rifle cartridge that is almost a direct copy of a wildcat cartridge developed around 1958 known as the 7mm/308. As these names would suggest, it is the .308 Winchester case necked down to accept 7 mm (.284) bullets with a small increase in case length. Of cartridges based upon the .308, it is the second most popular behind only the .243 Winchester. However, the .308 is more popular than both. In 1980, the Remington Arms company popularized the cartridge by applying its own name and offering it as a chambering for their Model 788 and Model 700 rifles, along with a limited-run series within their Model 7600 pump-action rifles during the early 2000s.
The .375 H&H Magnum, also known as .375 Holland & Holland Magnum, is a medium-bore rifle cartridge introduced in 1912 by London based gunmaker Holland & Holland. The .375 H&H cartridge featured a belt to ensure the correct headspace, which otherwise might be unreliable, given the narrow shoulder of the cartridge case. The cartridge was designed to use cordite which was made in long strands – hence the tapered shape of the case, which, as a beneficial side effect also helped in smooth chambering and extraction from a rifle's breech.
The .300 Winchester Magnum is a belted, bottlenecked magnum rifle cartridge that was introduced by the Winchester Repeating Arms Company in 1963. The .300 Winchester Magnum is a magnum cartridge designed to fit in a standard rifle action. It is based on the .375 H&H Magnum, which has been blown out, shortened, and necked down to accept a .30 caliber (7.62 mm) bullet.
The .444 Marlin (10.9×57mmR) is a rifle cartridge designed in 1964 by Marlin Firearms and Remington Arms. It was designed to fill in a gap left by the older .45-70 when that cartridge was not available in any new lever-action rifles; at the time it was the largest lever-action cartridge available. The .444 resembles a lengthened .44 Magnum and provides a significant increase in velocity. It is usually used in the Marlin 444 lever-action rifle. Currently, Marlin, who is now owned by Ruger Firearms, does not offer the .444 chambering in any of their rifles. It remains to be seen when or if they will bring the chambering back into production.
The .280 Remington, also known as the 7mm-06 Remington and 7mm Express Remington, was introduced in 1957 for the Remington model 740, 760, 721, and 725 rifles.
The 7mm Remington Magnum rifle cartridge was introduced as a commercially available round in 1962, along with the new Remington Model 700 bolt-action rifle. It is a member of the belted magnum family that is directly derived from the venerable .375 H&H Magnum. The original purpose of the belted magnum concept taken from the .300 H&H Magnum and .375 H&H Magnum, was to provide precise headspace control, since the sloping shoulders, while easing cartridge extraction, were unsuitable for this purpose. Improved cartridge extraction reliability is desirable while hunting dangerous game, in particular when a fast follow-up shot is required. The 7mm Remington Magnum is based on the commercial .264 Winchester Magnum, .338 Winchester Magnum, and .458 Winchester Magnum, which were based on the same belted .300 H&H Magnum and .375 H&H Magnum cases, trimmed to nearly the same length as the .270 Weatherby Magnum.
The 8mm Remington Magnum belted rifle cartridge was introduced by Remington Arms Company in 1978 as a new chambering for the model 700 BDL rifle. The 8mm Remington Magnum's parent case is the .375 H&H Magnum. It is a very long and powerful cartridge that cannot be used in standard length actions, such as those that accommodate the .30-06 Springfield.
The .264 Winchester Magnum is a belted, bottlenecked rifle cartridge. Except for the .244 H&H Magnum and .257 Weatherby Magnum, it is the smallest caliber factory cartridge derived from the 2.85 in (72 mm) Holland & Holland belted magnum case. It was introduced in the late 1950s and early 1960s with the .338 Winchester Magnum and the .458 Winchester Magnum as one of a family of short-cased 2.5 in (64 mm) belted magnum cartridges developed by Winchester based on the .375 Holland & Holland parent case. It was officially introduced to the public by Winchester in 1959. After many years of dwindling use it began enjoying a mild resurgence in popularity in the mid-2000s among long range rifle enthusiasts and reloaders due to the high ballistic coefficient of the heavier 6.5mm bullets and increasing popularity of cartridges such as 6.5mm Creedmoor, .260 Remington, 6.5 Grendel, benchrest and wildcat cartridges in 6.5mm.
The .244 Holland & Holland Magnum cartridge was created in 1955 in Great Britain by deerstalker and rifle-maker David Lloyd of Pipewell Hall, Northamptonshire and Glencassley in Sutherland, Scotland, and is not to be confused with the smaller-cased and much milder 6 mm Remington. Stalking on extremely steep deer forests such as his own at Glencassley, Lloyd was in search of a "canyon rifle" cartridge that would shoot exceptionally fast and with a very flat trajectory across deep valleys and over distances out to 300 yards (270 m) and more, to make range estimation less critical for accurate bullet placement, and to deliver a hard-hitting bullet weighing a minimum of 100 grains. The .244 H&H Magnum easily met these criteria.
.22 caliber, or 5.6 mm, refers to a common firearms bore diameter of 0.22 inch (5.6 mm) in both rimfire and centerfire cartridges.
The .375 Ruger (9.5×65.5mm) is a rimless, standard-length rifle cartridge designed for hunting large, dangerous game. It is designed to provide an increase in performance over the .375 H&H cartridge within the context of a standard-length rifle action. The cartridge was designed in partnership by Hornady and Ruger. In 2007, it was released commercially and chambered in the Ruger Hawkeye African and the Ruger Hawkeye Alaskan rifles.
The .400 H&H Magnum also known as .400 Holland & Holland Magnum is a belted rimless bottlenecked cartridge introduced by Holland & Holland. The cartridge was released together with the .465 H&H Magnum in 2003. It is based on the .375 H&H Magnum case.
The 7mm Winchester Short Magnum is a centrefire cartridge developed in partnership with Browning Arms Company and Winchester ammunition, making its debut and introduced to the shooting public in 2001. It is a member of the Winchester Short Magnum family of cartridges.
The .280 Ackley Improved was the result of the .280 Remington case modification by P.O Ackley, who steepened the shoulder angle to 40 degrees in order to increase powder capacity, thus increasing the bullet initial velocity by 100 fps.
