Mateba Autorevolver

The Mateba Model 6 Unica (often known simply as the Mateba or the Mateba Autorevolver) is a semi-automatic revolver, one of only a few of this type ever produced. It was developed in Italy and sold by the Mateba company. Emilio Ghisoni (d. 2008) is listed as the owner of US Patent #4,712,466 which details the operation of the weapon.

Design
The Mateba Model 6 uses the recoil from firing to rotate the cylinder and cock the hammer, unlike conventional revolvers, which depend on the user physically pulling the trigger and/or cocking the hammer to actuate the weapon's mechanism of operation.

The Mateba Autorevolver's barrel alignment is different from most other revolvers. The barrel is aligned with the bottom of the cylinder instead of the top. This lowers the bore axis (line of the barrel) which directs the recoil in line with the shooter's hand thereby reducing the twisting motion or muzzle flip of normal revolvers.

The gun's entire upper assembly (barrel, cylinder and frame) are mounted on rails on the lower frame, which houses the trigger, hammer, and grip, and recoils 1/2 of an inch, or 12.7mm, on firing. The rearward motion of the upper assembly cocks the hammer, and the cylinder is rotated on the forward stroke.

Variants
The following are variants of the Mateba revolver:

Defense - 4" Barrel, .357 Magnum Home Protection - 5" Barrel, .44 Remington Magnum Dynamic Sportiva - Either 5" or 6" barrel, .357 Magnum Hunter - 8 3/8" Barrel, .357 Magnum (.38 Special) and .44 Remington Magnum (.44 S&W Special)

In addition, their barrels can be changed with interchangeable 3", 4", 5", 6", 7" and 8" inch barrels.

Mateba Grifone
Also available was the Mateba Grifone, which mated an 18-inch barrel, hand guard and butt stock to the Autorevolver's frame and action. It was available in .357 Magnum and .44 Magnum. A version in .454 Casull was available which also allowed .45 Colt ammunition to be fired.

Multiple cartridge capabilities


Mateba Autorevolvers chambered in .357 Magnum can be loaded with .38 Special ammunition but typical .38 Special loads do not have enough power to fully cycle the recoil mechanism although the weapon will still function with a double action trigger pull. There are two optional recoil springs designed specifically for .38 Special cartridges that can be installed by the operator to overcome this problem (.38 Special and .38 Wadcutter).

Replacing the spring requires the removal of the slide assembly, which is blocked by a retaining pin held in place by a small set screw in the triggerguard. The barrel shroud acts as the spring keeper and guide rod bushing.