Re: Sig 556 or colt ?
I recently took the plunge and bought a Sig 556 Classic. It really seems like it is just a cross between an AK and AR platform. I heard a lot about it's reliability; however, on my first trip to the range I had four malfunctions using 20 round pmags.
The first was a failure to feed with standard 55gr Lake City ammo. It seemed to me that the Sig tries to solve timing issues with just brute force. The bolt speed seems really fast, and empties fly ridiculously far.
I then ran 77gr Black Hills ammo through it and had three failures to eject. In all malfunctions it chewed the brass up something fierce.
My accuracy with both types of ammo was in the 2 - 3 moa range, sometimes less, sometimes more. The fit between the upper and lower receivers is extremely loose, and in my dry fire practice on this gun you can actually witness slight movement between the two.
Don't get me wrong, I haven't made my mind up on the Sig, and I think with some work I might be able to squeeze some more accuracy out of it... but if you plan on reloading at all, I would go with the Colt.