The gas piston pushes the bolt carrier rearward where it is returned to the forward and locked position by a spring.

All SIG516 models except the Marksman are equipped with 16-inch (406 mm) barrels shrouded by a free-floating M1913 Picatinny rail, as well as flip-up iron sights (BUIS) made by SIG Sauer.

It is built to pass the NATO test protocol “Over the Beach”, meaning the SIG516 is designed to fire safely as quickly as possible after being submerged in water.

The SIG716 is a battle rifle variant,[5] which is based on the same design, but is chambered for the larger 7.62x51mm NATO round and uses SR-25 pattern magazines.

This operating system reduces carbon fouling, excessive heat and unburned powder in the action, ensuring further improved reliability and function.

This Stoner bolt and carrier piston operating system has helped SIG Sauer to bring down the cost of manufacturing and pushing more sales of 716i, whilst also achieving a weight reduction.

[11] Sig Sauer appears to have discontinued SIG716 and SIG716 G2 models, since the company stopped displaying these products in their website, while they continue to sell magazines and spare parts in their online store.

[citation needed] The 716i has been recognized as the best AR-10 rifle for the year 2020, by readers' choice voting of Ballistic magazine.