[MasterGunner01]

This SR-556 was not exposed to salt water, so after it dries out, given some lubricant, it should function like a good sewing machine. the optics might also work if allowed to dry out completely. Any surface corrosion will come off when exposed to some gun oil. Now, salt water could definitely cause problems, but that depends on the length of immersion and salinity of the water. The SR-556 and other AR-15 clones stand up to living at the bottom of the lake for some time. If there was Mil-Spec ammo (M193 [55-grain projectile] or M852 [62-projectile]) in the standard 30-round magazine, the SR-556 will probably still shoot. Mil-Spec 5.56 NATO ammo is waterproof.

[rdcbn]

The barrel is chrome lined so a little surface rust is no big thing.

A good cleaning and lubrication and it should work just fine.