The Sig 550 is basically a Swiss copy of the AK and the Sig 556 is the Sig USA derivative of the 550. Well, the 556R is the 7.62x39 derivative of the Sig 556 that takes factory AK mags. Basically, they've come full circle. If the movie Inception were a gun, it would be this one. I've got other Sig 556s as well and a plethora of parts and accessories if you've got one and are looking for anything. 


For more pictures or if you have any questions, please text or email me, as I don't check this often. 


303-731-6009


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