Rimfire firearm receiver

A receiver assembly according to claim-1 in which

• said cartridge feeding ramp is compressed between the inward end of the barrel and the end of the bolt engaged in the bolt engaging opening of the receiver during the cartridge firing sequence to preload the bolt axially and absorb vibrations between the fixed barrel and the movable bolt components,
• said cartridge feeding ramp comprising
• a generally cylindrical member formed of flexible material received in said cylindrical cavity between the inward end of said barrel and the bolt engaging opening and having a cylindrical side wall and front and back ends with a central conical opening extending inwardly from the back end receive a cartridge therethrough and barrel engaging means on the front end for engaging the inward end of the barrel to prevent rotation of said cylindrical member in said cavity relative to said receiver,
• said cylindrical member positioned with the smaller end of the conical opening adjacent the inward end of said barrel in axial alignment with the longitudinal barrel bore and the larger end of said conical opening adjacent the bolt engaging opening in said receiver and axially aligned with the longitudinal receiver chamber, whereby
• the conical opening provides a guide for feeding a cartridge into the bore of the barrel to be fired and said cylindrical member is compressed between the inward end of the barrel and the end of the bolt engaged in the receiver bolt engaging opening during the cartridge firing sequence to axially preload the bolt and absorb vibrations between the fixed barrel and the movable bolt components.

A receiver assembly for a rimfire firearm having an elongated longitudinal chamber adapted to receive a cylindrical barrel within one end thereof comprising;

• means forming a bolt engaging opening in the longitudinal chamber of the receiver spaced axially from the inward end of the barrel to form a cylindrical cavity therebetween,
• a bolt slidably and rotatably mounted in the longitudinal bore of the receiver and having a generally elliptical head portion at the front of said bolt which forms diametrically opposed locking lugs to be slidably received through the bolt engaging opening and engaged therewith upon rotation,
• a tubular cartridge extractor-guide rotatably mounted on the forward end of said bolt to allow said bolt to rotate approximately 90.degree. relative thereto,
• cartridge receiving and gripping means on the front end of said extractor-guide which receive and releasably retain the rim of a cartridge on the front end of said bolt while being carried to a firing position,
• said receiving and gripping means engaging the inward end of said barrel upon sufficient forward movement of said bolt to release said cartridge and thereafter prevented by the engagement from rotating with said bolt as it is rotated to a firing position in the bolt retaining opening of the receiver, and
• said receiving and gripping means receiving and releasably retaining the rim of said cartridge case after firing and said bolt is being retracted from the forward position to extract the casing from the firing chamber.

A sliding and rotating bolt for a rimfire firearm having a receiver assembly having an elongated cylindrical chamber and a rifle barrel secured in the forward end thereof,

• said bolt comprising
• an elongate cylindrical body adapted to be slidably and rotatably mounted within said elongated chamber having a bolt engaging opening spaced axially from the inward end of the firearm barrel,
• a generally elliptical head portion forward of said cylindrical body forming diametrically opposed locking lugs slidably received through the bolt engaging opening when assembled and engaged therewith upon rotation, and
• a tubular cartridge extractor-guide rotatably mounted on the forward end of said bolt to allow rotation approximately 90.degree. relative thereto,
• cartridge receiving and gripping means on the forward end of said extractor-guide to receive and releasably retain the rim of a cartridge on the front end of said bolt while being carried by said bolt to a firing position,
• said receiving and gripping means engaging the inward end of said barrel upon sufficient forward movement of said bolt to release said cartridge and thereafter prevented by the engagement from rotating with said bolt as it is rotated to a firing position in the bolt retaining opening of the receiver, and
• said receiving and gripping means receiving and releasably retaining the rim of said cartridge case after the cartridge has been fired and said bolt is being retracted from the forward position to extract the casing from the firing chamber.