A barrel mounting system to mount a barrel to a barrel mount of a firearm body includes a mount receiver secured to the barrel mount. The mount receiver includes axial channels and receiver threads disposed on an interior surface. The system further includes a barrel sleeve disposed around the barrel proximal to the proximal end of the barrel. The barrel sleeve includes sleeve threads disposed near a proximal end on an exterior surface and sized to slide through the axial channels and, when rotated, to engage the receiver threads. The system further includes a barrel collar disposed around the barrel and secured to the barrel and to limit the axial position of the barrel sleeve.