Alright, this doesn't seem bad, but I spotted a few problems, the first thing that jumped out at me (might seem like nitpicking a bit) But you stated your character was "6 foot tall, 200 pounds" and then followed with "slim and muscular" first of all, 200 pounds is a lot, probably over the weight limit in the army, but let's say it wasn't, it still doesn't make sense to call him "slim" so either heavy or slim, which one?
Your weapons and equipment seem mostly in order, your brief history is where I scratch my head though. You say he was 18, and then two years later involved in a battle in which he was one of the only few survivors, gathered intelligence along the way, and helped win it... Which battle was this again? In Ledgend's lore, he said the US mostly remained back, and the one major battle they had, they lost, at Kurmuk. If this was a war BEFORE their recession, your guy is bound to be very old for military standards. Very few last in the army for 5 years (at least), especially 18 year olds. Also, you aren't just 'promoted' after a battle, many privates who serve valiantly on the field come out of the battle with the same rank, even if they were some of the last men standing, to go further, he had to be a recruit at this time... Did he jump a huge number of ranks with one battle?
Further put... Why is this here:
"His family served in American inolved war since WWI."
It... Doesn't help the story, you just kind of said his family has military lineage... Okay then. Further, besides the Alexsander incident, Russia didn't really have horrible relations with the US, let alone them being in a state of "Shoot any US/Russians on sight" so why was your guy betrayed again? Further, how did he escape? And what purpose did he have being in Russia? Russia is obviously armed quite well, even if they were enemies, there's no logical way he could escape an entire military without being spotted.
Besides that, it seems fine. Work on what I said a bit.