The rimmed cartridge, sometimes called flanged cartridge, is the oldest of the types and has a rim that is significantly larger in diameter than the base of the cartridge. Rimmed cartridges use the rim to hold the cartridge in the chamber of the firearm, with the rim serving to hold the cartridge at the proper depth in the chamber—this function is called "headspacing". Because the rimmed cartridge headspaces on the rim, the case length is of less importance than with rimless cartridges. This allows some firearms chambered for similar rimmed cartridges to safely chamber and fire shorter cartridges.
Rimmed cartridges generally do not work quite as well in firearms that feed from a box magazine, since the magazine must be carefully loaded so that the rim from each successive case is loaded ahead of the round beneath it, so the round will not snag on the rim of the cartridge below it as the bolt strips it out of the magazine.
.17 Hornady Magnum Rimfire, commonly known as the .17 HMR, is a rimfire rifle cartridge developed by the ammunition company Hornady in 2002. It was developed by necking down a .22 Magnum case to take a .17 caliber (4.5 mm) projectile. Commonly loaded with a 17 grain (1.1 g) projectile, it can deliver muzzle velocities in excess of 775 m/s (2,650 ft/s).
The .17 Remington was introduced in 1971 by Remington Arms Company for their model 700 rifles. It is based on the .223 Remington case necked down to .172 in (4.37 mm), with the shoulder moved back. It was designed exclusively as a varmint round, though it is suitable for smaller predators. There are those such as P.O. Ackley who used it on much larger game, but such use is not typical. Extremely high initial velocity (over 4000 ft/s 1200 m/s), flat trajectory and very low recoil are the .17 Remington's primary attributes. It has a maximum effective range of about 440 yards (400 m) on prairie dog-sized animals, but the small bullet's poor ballistic coefficients and sectional densities mean it is highly susceptible to crosswinds at such distances.
The 223 Remington is a rifle cartridge, originally developed in 1957 as a commercial hunting bullet for varmint hunting. The first rifle chambered for it came out in 1963. It has continued to be a popular civilian small game hunting cartridge. Though it finds occasional use on medium game, this is not recommended and is illegal in at least ten U.S. states and the United Kingdom, where the .243 Winchester or similar cartridges are the smallest bore cartridges that are legal for hunting deer. A military version, M193, with a 55-gr full metal jacket bullet was used by the United States Army in the M16 rifle. The 5.56×45mm NATO was also developed from the 223 Remington.
The .243 Winchester (6.2×52mm) is a popular sporting rifle cartridge. Developed as a versatile short action cartridge to hunt both medium game and small game alike, it "took whitetail hunting by storm" when introduced in 1955, and remains one of the most popular whitetail deer cartridges. It is also commonly used for harvesting blacktail deer, pronghorns and mule deer with heavier rounds, and is equally suited to varmint hunting with lighter rounds. The .243 is based on a necked down .308 Winchester, introduced only three years earlier. Expanding monolithic copper bullets of approximately 80 to 85 grains or traditional lead rounds of 90 to 105 grains with controlled expansion designs are best suited for hunting medium game, while lighter rounds are intended for varmints. In at least ten U.S. states and the United Kingdom, the .243 or similar cartridges are the smallest bore cartridges that are legal for hunting deer. The cartridge can be extremely accurate to 300 yards (270 m) and beyond, but may not retain enough terminal energy to reliably drop medium game at that distance. Highly experienced hunters use the .243 Winchester to routinely drop bucks up to 250 pounds (110 kg), while young and/or female hunters can be just as capable with the .243 because of its very low recoil yet high velocity. Besides hunting applications, the cartridge is popular with target and metallic silhouette shooters for those same recoil and velocity properties, with superb accuracy.The .243 Winchester has regularly made the top five of rankings for "Best Whitetail Deer Hunting Cartridges" from sources such as Field and Stream and Outdoor Life, and its widespread popularity (called the "whitetail hunter's favorite" by the Browning Arms Company and "American favorite" by American Rifleman) assures chamberings in newly manufactured offerings of not only bolt-action rifles, but also semiautomatic rifles (e.g., Browning BAR), lever action rifles (e.g., Henry Long Ranger), and pump action rifles (e.g., Remington 7600). Gun Digest estimates that (as of the end of 2018) the .243 Winchester is the second-most popular of all hunting rifle chamberings (after the long action .30-06). Commentators such as popular ammunition author Chuck Hawks have opined that the .243 Winchester (as a "6mm NATO" round) should replace the 5.56×45mm NATO (.223 Remington) for most United States Armed Forces use cases but the .243 has, as of 2021, never been used as a military cartridge.