.460 Rowland
Encyclopedia
The .460 Rowland is a proprietary cartridge intended to attain .44 Remington Magnum
level velocities with a M1911
-pattern semi-automatic pistol
. The cartridge concept originated with Johnny Rowland, the host of "The Shooting Show". In 1996, Rowland worked with Starline Brass to finalize the physical dimensions of the cartridge, then later with Clark Custom Guns to design a conversion kit for specific versions of the M1911. First production shipments of ammunition and conversion kits were in 1998.
. However, the overall cartridge length of the .460 Rowland is the same as the .45 ACP as the bullet is seated a bit deeper. This means the practical case capacity for both cartridges is identical. Case length for the .45 ACP is 0.898 inches (2.3 cm) and cartridge overall length is 1.275 inches (3.2 cm). Case length for the .460 Rowland is 0.955 inches (2.4 cm) and cartridge overall length is 1.275 inches (3.2 cm). The purpose of the extended case length is to prevent the high pressure .460 Rowland from being chambered in a standard firearm chambered for the low pressure .45 ACP, similar to the relationship between the .357 Magnum
and the .38 Special
. The overall cartridge length restriction imposed on both cartridges is established by the cartridge length capacity of the M1911
design.
There are two key elements to the .460 Rowland concept. The first is a sharp increase in cartridge maximum pressure over the .45 ACP and .45 Super. Maximum Average Pressure is: 45 ACP (21,000 PSI), .45 ACP +P (23,000 PSI), .45 Super
(28,000 PSI), .460 Rowland (40,000 PSI). The result of this pressure increase is a potential for 185 gr bullets to achieve 1500 ft/s (457.2 m/s) MV and 230 gr bullets to achieve 1340 ft/s (408.4 m/s). The second element, in regard to M1911 type autoloaders, is to dampen or reduce the velocity of the slide to a manageable level.
. The increase in slide velocity over a standard .45 ACP, or even a .45 Super round, cannot be properly controlled with an increase in recoil spring rate alone. A conversion requires a compensator to delay unlocking of the M1911 action until pressure has fallen to more manageable levels. Without a compensator, slide or frame failure would result.
Conversion kits co-developed by Wild West Guns and Jonny Rowland for the Smith & Wesson M&P, Glock and Springfield Armory Tactical striker type pistols, due to locking system differences, do not require use of a compensator. Slide velocity in these converted firearms is controlled with a change to the recoil spring alone. Subsequently, the converted firearm is lighter and more compact than a converted 1911 type.
Either type of modified autoloader theoretically can still fire .45 ACP cartridges; however, head spacing would not be at the case mouth, which is the proper location. Instead, the cartridge would be held in position by the gun's extractor. Additionally, the bullet would be unsupported in the forward 1/16" portion of the chamber so accuracy would suffer and high recoil spring rates intended for the .460 Rowland cartridge would prevent reliable cycling. Since the conversion is not permanent, the pistol's owner is free to exchange their .45 ACP and .460 Rowland barrel assemblies.
Pistols and carbines based on a closed-bolt semiautomatic version of the MAC-10
design are available in .460 Rowland.
Some revolvers may be modified for use with the .460 Rowland. Typical examples are the Ruger Blackhawk
and Smith & Wesson Model 25/625 that were originally chambered for the .45 ACP. The conversion of revolvers requires deepening the chambers, and is effectively permanent, unless the owner has a replacement cylinder fitted. Dan Wesson also produced for several years a revolver specifically made for the 460 Rowland, which would also chamber .45 ACP, .45 Super and .45 Winchester Magnum
(all require moon clips).
.44 Magnum
The .44 Remington Magnum, or simply .44 Magnum, is a large-bore cartridge originally designed for revolvers. After introduction, it was quickly adopted for carbines and rifles...
level velocities with a M1911
M1911
The M1911 is a single-action, semi-automatic, magazine-fed, and recoil-operated handgun chambered for the .45 ACP cartridge. John M. Browning designed the firearm which was the standard-issue side arm for the United States armed forces from 1911 to 1985. The M1911 is still carried by some U.S....
-pattern semi-automatic pistol
Pistol
When distinguished as a subset of handguns, a pistol is a handgun with a chamber that is integral with the barrel, as opposed to a revolver, wherein the chamber is separate from the barrel as a revolving cylinder. Typically, pistols have an effective range of about 100 feet.-History:The pistol...
. The cartridge concept originated with Johnny Rowland, the host of "The Shooting Show". In 1996, Rowland worked with Starline Brass to finalize the physical dimensions of the cartridge, then later with Clark Custom Guns to design a conversion kit for specific versions of the M1911. First production shipments of ammunition and conversion kits were in 1998.
Design
The .460 Rowland case is approximately 1/16" (0.0625 inch (0.15875 cm)) longer than a conventional .45 ACP.45 ACP
The .45 ACP , also known as the .45 Auto by C.I.P., is a cartridge designed by John Browning in 1904, for use in his prototype Colt semi-automatic .45 pistol and eventually the M1911 pistol adopted by the United States Army in 1911.-Design and history:The U.S...
. However, the overall cartridge length of the .460 Rowland is the same as the .45 ACP as the bullet is seated a bit deeper. This means the practical case capacity for both cartridges is identical. Case length for the .45 ACP is 0.898 inches (2.3 cm) and cartridge overall length is 1.275 inches (3.2 cm). Case length for the .460 Rowland is 0.955 inches (2.4 cm) and cartridge overall length is 1.275 inches (3.2 cm). The purpose of the extended case length is to prevent the high pressure .460 Rowland from being chambered in a standard firearm chambered for the low pressure .45 ACP, similar to the relationship between the .357 Magnum
.357 Magnum
The .357 S&W Magnum , or simply .357 Magnum, is a revolver cartridge created by Elmer Keith, Phillip B. Sharpe, Colonel D. B. Wesson of firearms manufacturer Smith & Wesson, and Winchester. It is based upon Smith & Wesson's earlier .38 Special cartridge. The .357 Magnum cartridge was introduced in...
and the .38 Special
.38 Special
The .38 Smith & Wesson Special is a rimmed, centerfire cartridge designed by Smith & Wesson. It is most commonly used in revolvers, although some semi-automatic pistols and carbines also use this round...
. The overall cartridge length restriction imposed on both cartridges is established by the cartridge length capacity of the M1911
M1911
The M1911 is a single-action, semi-automatic, magazine-fed, and recoil-operated handgun chambered for the .45 ACP cartridge. John M. Browning designed the firearm which was the standard-issue side arm for the United States armed forces from 1911 to 1985. The M1911 is still carried by some U.S....
design.
There are two key elements to the .460 Rowland concept. The first is a sharp increase in cartridge maximum pressure over the .45 ACP and .45 Super. Maximum Average Pressure is: 45 ACP (21,000 PSI), .45 ACP +P (23,000 PSI), .45 Super
.45 Super
The .45 Super is a smokeless powder center fire metallic firearm cartridge developed in 1988 by Dean Grennell, a well-known writer in the firearms field as well as managing editor of Gun World magazine...
(28,000 PSI), .460 Rowland (40,000 PSI). The result of this pressure increase is a potential for 185 gr bullets to achieve 1500 ft/s (457.2 m/s) MV and 230 gr bullets to achieve 1340 ft/s (408.4 m/s). The second element, in regard to M1911 type autoloaders, is to dampen or reduce the velocity of the slide to a manageable level.
Conversions
M1911 autoloaders converted for this cartridge require a compensatorMuzzle brake
Muzzle brakes and recoil compensators are devices that are fitted to the muzzle of a firearm or cannon to redirect propellant gases with the effect of countering both recoil of the gun and unwanted rising of the barrel during rapid fire...
. The increase in slide velocity over a standard .45 ACP, or even a .45 Super round, cannot be properly controlled with an increase in recoil spring rate alone. A conversion requires a compensator to delay unlocking of the M1911 action until pressure has fallen to more manageable levels. Without a compensator, slide or frame failure would result.
Conversion kits co-developed by Wild West Guns and Jonny Rowland for the Smith & Wesson M&P, Glock and Springfield Armory Tactical striker type pistols, due to locking system differences, do not require use of a compensator. Slide velocity in these converted firearms is controlled with a change to the recoil spring alone. Subsequently, the converted firearm is lighter and more compact than a converted 1911 type.
Either type of modified autoloader theoretically can still fire .45 ACP cartridges; however, head spacing would not be at the case mouth, which is the proper location. Instead, the cartridge would be held in position by the gun's extractor. Additionally, the bullet would be unsupported in the forward 1/16" portion of the chamber so accuracy would suffer and high recoil spring rates intended for the .460 Rowland cartridge would prevent reliable cycling. Since the conversion is not permanent, the pistol's owner is free to exchange their .45 ACP and .460 Rowland barrel assemblies.
Pistols and carbines based on a closed-bolt semiautomatic version of the MAC-10
MAC-10
The MAC-10 is a highly compact, blowback operated machine pistol developed by Gordon B. Ingram in 1964.-Design:The M-10 was built predominantly from steel stampings...
design are available in .460 Rowland.
Some revolvers may be modified for use with the .460 Rowland. Typical examples are the Ruger Blackhawk
Ruger Blackhawk
The Ruger Blackhawk is a 6-shot or 8-shot, single-action revolver manufactured by Sturm, Ruger. It is produced in a variety of finishes, calibers, and barrel lengths.-History:In the early 1950s, Westerns were popular in movies and television...
and Smith & Wesson Model 25/625 that were originally chambered for the .45 ACP. The conversion of revolvers requires deepening the chambers, and is effectively permanent, unless the owner has a replacement cylinder fitted. Dan Wesson also produced for several years a revolver specifically made for the 460 Rowland, which would also chamber .45 ACP, .45 Super and .45 Winchester Magnum
.45 Winchester Magnum
The .45 Winchester Magnum is a .45 caliber rimless cartridge intended for use in semi-automatic pistols. The cartridge is a stretched version of the .45 ACP with additional strengthening in the web area to accommodate the higher operating pressure...
(all require moon clips).
See also
- .45 GAP.45 GAPThe .45 G.A.P. pistol cartridge was designed by Ernest Durham, an engineer with CCI/Speer, at the request of firearms manufacturer Glock to provide a cartridge that would equal the power of the .45 ACP but was shorter to fit in a more compact handgun, and with a stronger case head to reduce the...
- .45 Winchester Magnum.45 Winchester MagnumThe .45 Winchester Magnum is a .45 caliber rimless cartridge intended for use in semi-automatic pistols. The cartridge is a stretched version of the .45 ACP with additional strengthening in the web area to accommodate the higher operating pressure...
- .45 Super.45 SuperThe .45 Super is a smokeless powder center fire metallic firearm cartridge developed in 1988 by Dean Grennell, a well-known writer in the firearms field as well as managing editor of Gun World magazine...
- .44 Magnum.44 MagnumThe .44 Remington Magnum, or simply .44 Magnum, is a large-bore cartridge originally designed for revolvers. After introduction, it was quickly adopted for carbines and rifles...
- List of handgun cartridges
- 11 mm caliber11 mm caliberThis article lists firearm cartridges which have a bullet in the through caliber range.All measurements are in millimeters .-Pistol cartridges:-Revolver cartridges:-Rifle cartridges:-See also:...