Abstract: An orthopaedic surgical instrument includes a patella trial and drill guide that may be used to both perform a surgical trial of the patellofemoral joint and guide the surgeon in drilling a number of anchor holes in the patella of the patient.

Abstract: A take-down rifle is described that can be separated into two halves to allow the rifle to be transported, cleaned, etc. easier. The takedown rifle includes a takedown mechanism that is used to couple the two halves of the rifle together. The takedown mechanism may move between a first position where the takedown mechanism holds the two halves together and a second position where the two halves are released. In one embodiment, the takedown mechanism may include a securing member that is selectively moved into and out of a recess in the barrel to hold and release the two halves. The securing member may be moved into and out of the recess with a lever, threaded fastener, or the like.

Abstract: A take-down rifle is described that can be separated into two halves to allow the rifle to be transported, cleaned, etc. easier. The takedown rifle includes a takedown mechanism that is used to couple the two halves of the rifle together. The takedown mechanism may move between a first position where the takedown mechanism holds the two halves together and a second position where the two halves are released. In one embodiment, the takedown mechanism may include a securing member that is selectively moved into and out of a recess in the barrel to hold and release the two halves. The securing member may be moved into and out of the recess with a lever, threaded fastener, or the like.

Abstract: A shotgun includes a gas-operated action. The gas operated action includes a cylinder having at least one wall, a piston, and a resilient member. The resilient member is positioned between the piston and the wall of the cylinder to prevent high pressure gas from escaping between the piston and the wall of the cylinder. The resilient member and any surface that the resilient member is in contact with do not move relative to each other when the piston moves.

Abstract: An adjustable comb apparatus for firearms involves a base mounted within the stock of a firearm, a pair of servo-clamps adjustably secured within the base, a comb which has a pair of pins which are slidably received by the servo-clamps, and a locking screw which secures the comb at a desired position relative to the firearm stock. The servo-clamps allow the comb to be adjusted simultaneously in a cast direction and in a vertical direction. A single locking screw is rotated to secure the adjustable comb in the desired orientation.