Abstract: Modifications are provided in the structure of firearms such as breech-loading revolver handguns. Traditionally, these firearms are constructed with mating surfaces in face to face contact, which surfaces must be separated for loading. Where foreign particles are trapped between the flat mating surfaces on closing, jamming results. In one aspect of the invention, these flat mating surfaces are provided with cavities, so that any such foreign matter will fall into the cavities and not prevent the closing of the firearm mechanism after loading. In another aspect of the invention, a series of small vee-type notches, discernible by touch, are formed around the rear edge of a rotary magazine of cartridge cylinder, in a descending sequence in direction opposite to the operative direction of rotation of the rotary magazine when in battery.

Abstract: Modifications are provded in the structure of firearms such as breech-loading revolver handguns. Traditionally, these firearms are constructed with mating surfaces in face to face contact, which surfaces must be separated for loading. Where foreign particles are trapped between the flat mating surfaces on closing, jamming results. In one aspect of the invention, these flat mating surfaces are provided with cavities, so that any such foreign matter will fall into the cavities and not prevent the closing of the firearm mechanism after loading. In another aspect of the invention, a series of small vee-type notches, discernible by touch, are formed around the rear edge of a rotary magazine or cartridge cylinder, in a descending sequence in direction opposite to the operative direction of rotation of the rotary magazine when in battery.