Basically, the AK-47 is the Russian's improvement on the German's MP44. If you take a look a the two, they look remarkably similar.....Russian Ingenuity my Arse. The AK was designed to be able to be fixed in any Afghani Mud Hut, or bat cave, and does its task to the Letter. It is a very solid weapon, with a good action. The Bullet used makes alot of sense, a large stopping round, but with a much lower range than the 7.62 NATO. It is also a takeoff of the German "Kurz" round, which had a very short casing for the typical 7.92mm round of the day. Expected to be used at ranged under 400m. German weapon designers were way ahead of any Allied concepts, and we seem to be following what they were doing back before WW2, today. When do you take a pop at someone over 400m? The AK family is NATO's lost chance. Though the AK-47 may be crude, its younger sibling, the AK-74 is a much improved weapon. Firing the Warsaw Pact's version of NATO's 5.56mm round,their 5.45mm, it is again meant for closer ranges, which is what seems to be prevailing conflict ranges of this day.
So AK-74 vs C7? There is about a 25 year design difference, so you really cant compare the two. Even if you take the latest version of the 74, against the latest verson of the C7, there is still a 30 year difference (The C7A2 being designed shortly after the turn of the Millenium).