.460 Rowland

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.460 Rowland
TypePistol
Place of originUnited States
Production history
DesignerJohnny Ray Rowland
Produced1998 – Present
Specifications
Bullet diameter.451 in (11.5 mm)
Case length.957 in (24.3 mm)
Overall length1.275 in (32.4 mm)
Primer typeLarge pistol
Ballistic performance
Bullet weight/typeVelocityEnergy
80 gr (5 g)3,050 ft/s (930 m/s)1,680 ft·lbf (2,280 J)
180 gr (12 g) JHP1,560 ft/s (480 m/s)1,000 ft·lbf (1,400 J)
230 gr (15 g) JHP1,340 ft/s (410 m/s)930 ft·lbf (1,260 J)
230 gr (15 g) FMJ1,340 ft/s (410 m/s)930 ft·lbf (1,260 J)
260 gr (17 g) FMJ1,150 ft/s (350 m/s)770 ft·lbf (1,040 J)
Test barrel length: 5.5 in
Source(s): .460 Rowland LLC
 
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.460 Rowland
TypePistol
Place of originUnited States
Production history
DesignerJohnny Ray Rowland
Produced1998 – Present
Specifications
Bullet diameter.451 in (11.5 mm)
Case length.957 in (24.3 mm)
Overall length1.275 in (32.4 mm)
Primer typeLarge pistol
Ballistic performance
Bullet weight/typeVelocityEnergy
80 gr (5 g)3,050 ft/s (930 m/s)1,680 ft·lbf (2,280 J)
180 gr (12 g) JHP1,560 ft/s (480 m/s)1,000 ft·lbf (1,400 J)
230 gr (15 g) JHP1,340 ft/s (410 m/s)930 ft·lbf (1,260 J)
230 gr (15 g) FMJ1,340 ft/s (410 m/s)930 ft·lbf (1,260 J)
260 gr (17 g) FMJ1,150 ft/s (350 m/s)770 ft·lbf (1,040 J)
Test barrel length: 5.5 in
Source(s): .460 Rowland LLC

The .460 Rowland is a proprietary cartridge which attains true .44 Magnum level velocities when fired from a number of popular semi-automatic pistols, revolvers, and rifles.[citation needed] The cartridge was designed and developed by Mr. Johnny Ray Rowland, host of "The Shooting Show", and remains the most successful[citation needed] independently developed cartridge in the world today[citation needed]. After first developing the new cartridge, Mr. Rowland worked with Starline Brass to finalize commercial production of the brass and later with Clark Custom Guns to develop the first commercially available .460 Rowland Conversions for specific versions of the M1911.[1] First production shipments of ammunition and conversions were made through these associations in 1998.[citation needed]

Contents

Design

The .460 Rowland case is approximately 1/16" longer than a conventional .45 ACP case but the overall cartridge length is the same, the bullet is simply seated deeper. 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. This is similar to the relationship between the .357 Magnum and the .38 Special.

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 second is to dampen or reduce the velocity of the slide in converted autoloading pistols to manageable levels. The first delivers magnum level performance and the second allows the cartridge to be easily and reliably fired from compact, light weight, high capacity, autoloading pistols of an ever increasing variety.[citation needed]

Conversions

Model 1911 pistol with .460 Rowland conversion. The 1.5" compensator works in conjunction with a 22 to 24 pound recoil spring to effectively control slide velocity and recoil.

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. Autoloaders properly converted to fire the mighty .460 Rowland Cartridge require a compensator or a ported barrel to insure reliable, long lasting, operation. This fact not withstanding, there continues to be customer demand for a "Stock-Looking" .460 Rowland Conversion; however, any effort to answer this demand is thus-far not supported by the Inventor. Mr. Rowland still maintains that a properly designed .460 Rowland Conversion requires an effective compensator to momentarily delay slide action until the very high pressures developed by his cartridge dissipate to more manageable levels. Without this compensation, slide or frame failure will result over time and reliability will suffer in the short term.[citation needed]

A properly compensated .460 Rowland Conversion will accurately and reliably fire .45 ACP, +P and .45 Super cartridges.[citation needed] The shorter .45 casings are held in position by the gun's extractor in much the same way as many highly accurate revolver cartridges are held in their long chambers by moon clips. Accuracy and power do not suffer as a result.[citation needed]

High quality[citation needed] 1911 auto-loading pistols are manufactured by many different companies and tolerances vary with each manufacturer. As a result, adjusting recoil spring tensions and identifying specific magazines that works best in each individual gun have always been necessary to insure optimum performance from this 112 year old design. These same considerations are no less important when converting these guns to fire .460 Rowland cartridges. Once installed, tested and adjusted in this manner, a 1911 / .460 Rowland Conversion will shoot .45 ACP, +P, Super and .460 Rowland cartridges accurately and reliably without ever having to revert to the factory barrel. Springfield XD / XDm, Glock-21 and Glock-30 auto-loaders and the Sig-Sauer Model 220 are all made by a single manufacturer so similar adjustments are not often needed when these guns are converted to fire the .460 Rowland.[2]

The Ruger Blackhawk and Smith & Wesson Model 25/625 can also be chambered to fire the .460 Rowland. These conversions require deepening the chambers, and is effectively permanent unless the owner has a replacement cylinder fitted. For several years Dan Wesson also made a revolver specifically made for the .460 Rowland, which would also chamber .45 ACP, .45 Super and .45 Winchester Magnum, as does the Smith & Wesson Model 25/625. Both guns use moon clips and are very accurate fire arms. [Citation; Mr. Johnny Ray Rowland & .460 Rowland LLC]

See also

References

External links