Abstract: The present disclosure is directed to firearms that can receive and fire bullets from ammunition with different cartridge case sizes. For example, the receiver may fire a bullet from either a short cartridge, a medium cartridge, or long cartridge after the short, medium, or long cartridge is received by a receiver of the firearm. This firearm may include a receiver portion and a bolt portion that lock together at different relative locations when cartridges of different lengths are received by the receiver portion. The receiver portion may include a first type of alignment retention features (e.g. protrusions) and the bolt portion may include a second type of alignment retention features (e.g. recessions). Once a firearm cartridge is located inside of the firearm, it may be fired based on the receiver and the bolt portions being locked together via physical engagement of the different types of alignment retention features.

Abstract: The present disclosure is directed to firearms that can receive and fire bullets from ammunition with different cartridge case sizes. For example, the receiver may fire a bullet from either a short cartridge, a medium cartridge, or long cartridge after the short, medium, or long cartridge is received by a receiver of the firearm. This firearm may include a receiver portion and a bolt portion that lock together at different relative locations when cartridges of different lengths are received by the receiver portion. The receiver portion may include a first type of alignment retention features (e.g. protrusions) and the bolt portion may include a second type of alignment retention features (e.g. recessions). Once a firearm cartridge is located inside of the firearm, it may be fired based on the receiver and the bolt portions being locked together via physical engagement of the different types of alignment retention features.