A mechanism system for fully and semi-automatic rifles

A mechanism system for fully and semi-automatic rifles comprising:

• a barrel which ensures that an ammunition hits a target at a desired caliber;
• a mechanism which carries firing systems and enables the ammunition to be driven from a magazine to the barrel;
• a cylindrical mechanism cover with a circular geometry in middle, which provides axial and linear bearing for the mechanism in order to reduce number of parts by combining functions of rail systems and, breech sleeve and breech insert in a single structure and to eliminate problems of loss of strength and linearity encountered in the rail systems by providing support during axial and linear movement with the mechanism;
• and
• a barrel counter nut and a barrel tightening bushing, which are used in the barrel assembly and ensure the barrel is securely fixed in order to prevent the barrel loosening and unraveling problems that may be caused by prolonged firing.