The Sig Sauer 516 Patrol 5.56mm semi-auto rifle brings desirable mechanical improvements to the popular AR platform. The adjustable gas piston operating system reduces debris in the chamber, allowing the rifle to run cooler and cleaner. Its 16” military grade barrel is nitride treated for protection against the elements. A free floating handguard allows for a wide variety of rifle accessories. All of this coupled with the Sig Sauer proprietary fully supported extractor make the Sig Sauer 516 Patrol 5.56mm semi-auto rifle one of the most advanced rifles available today.