| 主权项 |
1. A functional gas-operated modular firearm, comprising:
a barrel assembly removably attachable with a receiver assembly solely by moving a quick-release mechanism between a first position and a second position, wherein: the receiver assembly comprises: a long-stroke gas-operation system comprising a piston and longitudinally-extending operation rod mechanically attached with and adapted to move together with a bolt group through an operating cycle of firing, extracting, and ejecting a first round and chambering a second round; a trunnion having an opening adapted to removably receive and locate therein a chamber portion of the barrel assembly; the quick-release mechanism attached with the trunnion that when in the first position is adapted to lock the barrel assembly to the receiver assembly, and that when in the second position is adapted to release the barrel assembly from the receiver assembly; and the barrel assembly comprises: a chamber portion adapted to removably engage with the trunnion and to house the first and second rounds for firing when removably engaged with the trunnion; a longitudinally extending barrel portion adapted to direct the first and second rounds after firing, and supporting thereon a gas cylinder; one or more gas communication ports adapted to communicate to the gas cylinder high-pressure gas from the firing of the first and second rounds; the gas cylinder adapted to at least partially surround the piston of the long-stroke gas-operation system when the chamber portion is removably engaged with the trunnion, and to transmit to the piston high-pressure gas from the firing of the first and second rounds that causes the long-stroke gas-operation system to move through the operating cycle. |
