Paintball gun

A paintball gun, comprising:

• an air valve, being selectively moved to a first position or a second position;
• and
• a body portion, comprising a main body having a hollow receiving room, a first air bore and a second air bore, the body portion further comprising:
• a paintball hole, disposed at a predetermined position of the main body and communicating with the receiving room;
• an axle sleeve, having a first end and a second end, the first end tightly engaging with an inner wall of the main body, an air passage being axially disposed through the axle sleeve while the first air bore communicating the air passage with an inlet;
• and
• a bolt, being movable between a third position and a fourth position, the bolt comprising an inner rod and an outer sleeve, an outer diameter of at least a part of the inner rod being substantially equal to a bore diameter of the air passage such that the inner rod being axially-movably fit in the air passage, a bore diameter of the outer sleeve being not smaller than an outer diameter of the axle sleeve, between the inner rod and the outer sleeve being disposed a linkup so that the inner rod and the outer sleeve being coupled into a linkage relationship, the linkup being disposed close to one end of the bolt away from the first end of the axle sleeve, between the inner rod, the outer sleeve, the linkup and the axle sleeve being defined a projection passage, between the projection passage and the air passage being disposed an effusion passage, the effusion passage being selectively turned open or closed, at least a projection hole being axially penetrating the linkup and communicating the projection passage, at a predetermined position of an outer periphery of the outer sleeve being formed with an enlarged flange, between the flange, the outer sleeve and the main body being defined a first chamber, a contacting area between the first chamber and the flange being a first surface, an area of the first surface being larger than that of a radial profile of the inner rod, and the second air bore communicating the first chamber with the air valve;
• wherein, when the air valve is at the first position, the air valve communicates the inlet with the second air bore, such that air in the inlet flows into the first chamber via the second air bore, and into the air passage via the first air bore, the bolt is then pushed to the third position and shuts the effusion passage because the area of the first surface is larger than that of the radial profile of the inner rod, meanwhile, the paintball hole is opened for a paintball to drop into the receiving room;
• wherein, when the air valve is at the second position, the air valve communicates the second air bore with a first decompression bore, at the instant, the air in the first chamber is evacuated through the first decompression bore, and then the air in the air passage pushes the inner rod so as to further push the bolt to the fourth position and shut the paintball hole, meanwhile, the effusion passage is open for the air to evacuate from the projection passage and the projection hole so as to project the paintball.