The .500 Linebaugh is a .50 caliber handgun cartridge designed for use in revolvers. It is considered to be one of the most powerful handgun cartridges designed in terms of energy and throw weight.

History

The .500 Linebaugh cartridge was designed by John Linebaugh of Maryville Mo. in 1986. John Linebaugh had been converting .45 Colt

.45 Colt

The .45 Colt cartridge is a handgun cartridge dating to 1872. It began as a black powder revolver round developed for the Colt Single Action Army revolver, but is offered as a magnum level handgun hunting round in modern usage. This cartridge was adopted by the U.S. Army in 1873 and served as the...

 six-shooters to five-shot revolvers, thus offering a stronger cylinder which could withstand the firing of higher pressures .45 Colt ammunition. While this venture was successful, he continued to search for a more powerful cartridge which resulted in the .500 Linebaugh.

The cartridge case itself was designed by cutting off the .348 Winchester

.348 Winchester

The .348 Winchester is an American rifle cartridge. It was introduced in 1936, and developed for the Winchester Model 71 lever rifle. The .348 was one of the most powerful rimmed rounds ever used in a lever rifle.-Performance:...

 case to 1.405 in (35.7 mm), turning the rim to a diameter of 0.61 in (15.5 mm)and opening the case mouth the accept a .510 caliber (12.9 mm) bullet. The first revolvers converted to use the .500 Linebaugh were the Ruger Bisley and the Seville revolvers. Due to the demise of the Seville revolvers in the early 1990s all subsequent conversions have been carried out on revolvers based on the Ruger Bisley frame.

It was when the supply of .348 Winchester cases started running out that John Linebaugh began working on the .475 Linebaugh

.475 Linebaugh

The .475 Linebaugh is an extremely potent rimmed revolver cartridge developed by John Linebaugh in the late 1980s. The cartridge is based on the .45-70 Government case cut down to 1.5 inches and loaded with bullets weighing from to...

 which could be formed from the more available .45-70 Government cases. When the Winchester Model 1871 was reintroduced in the .348 Winchester the ability to form .500 Linebaugh cases became again feasible. Today, Starline and Buffalo Bore offer .500 Linebaugh cases which are not dependant on the supply of .348 Winchester cases.

Cartridge Design and Specifications

The .500 Linebaugh is a proprietary cartridge and thus has not been adopted my mainline firearms manufacturers. Currently no firearms manufacturers make revolvers specifically for this cartridge. Instead, gunsmiths such as John Linebaugh of Linebaugh Custom Six guns and Hamilton Bowen of Bowen Classic Arms convert pre-existing single action revolvers such as the Ruger Blackhawk and Bisley to fire the cartridge. Hamilton Bowen has been known to have converted the Ruger Redhawk double action revolver for use with this cartridge.

Due to the proprietary status of the cartridge neither the CIP nor SAAMI have published official specifications for the cartridge. As is the case, there can be some variations from gunsmith the gunsmith. No pressure standard has been published for the cartridge but according to Linebaugh pressures levels between 30000 psi (2,068.4 bar) and 35000 psi (2,413.2 bar) are considered safe it the converted revolvers.

The cartridge uses .510 in. (12.95 mm) diameter jacketed bullets or .511-.512 in. (12.98-13.01 mm) lead bullets.

Sporting Usage

The .500 Linebaugh was designed as a hunting cartridge but would also make excellent backup firearm in areas where large bears may be encountered; particularly in Alaska.. It was designed to fire a 440 gr bullet at 1300 ft/s (396.2 m/s). This particular loading generates 1650 ft·lbf (2,237.1 J) of energy making this one of the most powerful handgun cartridges put into production. In terms of energy, this is comparable to the .454 Casull

.454 Casull

The .454 Casull is a firearm cartridge, developed in 1957 by Dick Casull and Jack Fulmer. It was first announced in November 1959 by Guns & Ammo magazine. The basic design was a lengthened and structurally improved .45 Colt case...

cartridge. However, the .500 Linebaugh provides a larger diameter, heavier bullet with a comparable sectional density than the .454 Casull. As a hunting cartridge it is capable of taking any North American game animals and most African game species.