The present invention pertains generally to devices, or as commonly termed measures, for discharging a predetermined quantity of granular material such as, for example, gunpowder.
The most common measure used by those engaged in reloading of rifle cases and shotgun shells are of the crank-operated type having a rotatable component, either fixed or replaceable, which defines a powder receiving cavity. Crank operation rotates the cavity from a load receiving to a load discharging position. A recognized disadvantage of such measures is the fact that the powder is subjected to a degree of grinding during drum rotation which may significantly affect later shell or cartridge performance. A further drawback to rotary measures is the vibration which occurs during the shearing of a gunpowder granule. While slight, such vibration has a settling effect on the gunpowder to affect the density of the measured charge and the hopper carried powder to be subsequently measured.
To vary the measured amount of typical crank-operated rotary devices, the cavity defined by the rotor must be altered which usually entails the replacement or altering of the rotor at some inconvenience to the user.
Additionally known in the art are dipper-type measures which are simply a receptacle of a known volume affixed to the end of a handle. A still further measuring technique includes the use of powder scales which technique is considered too time consuming and tedious by most individuals engaging in reloading.
With attention now to the closest known prior art, U.S. Pat. Nos. 249,464; 309,088; 346,718 and 466,209 disclose measures for gunpowder wherein an amount is measured by deposit into a chamber jointly defined by telescopically joined tubes with provision made for axial adjustment of same varying the measured amount. Upper and lower gates regulate the intake and discharge of the measured amount.
U.S. Pat. No. 425,659 discloses a bottle filling machine utilizing telescopically engaged tubes each having an offset opening from an opening in the remaining tube with the tubes biased to a closed position by a spring confined between the tube ends.
U.S. Pat. No. 2,426,898 discloses a gunpowder measure having a rotary valve which releases gunpowder into an area defined by a stationary tube closed by the upper ends of a pair of telescoped tubes which pair of tubes provides a valve at their corresponding upper ends opened and closed upon rotation of one of said tubes. Threaded means are provided to simultaneously raise or lower the telescoped tubes to alter the size of the measuring chamber. A set screw acts on the adjustment screw.