Lots of folks that own centerfire semi-auto rifles expect to shoot them forever without cleaning the gas system. When I worked in the Browning Arms gunsmithing shop I can't tell you how many BAR's were sent in for repair when the only problem was a dirty gas system. Some were so dirty that the gas piston was frozen solid, requiring the use of a slide hammer to disassemble. Fortunately the end of the piston had an internal thread facilitating the use of the slide hammer.
