From publisher blurb:
Finally a book that gives real world info about military small arms that is A) written by someone who has actually used them and B) doesn't cost a million bucks!
Michael Nunn is a veteran of the 101st Airborne, and served during the first Gulf War. He has drawn on his extensive experience with these weapons to provide you with a realistic assessment of their capabilities.
The book was designed specifically as an enhancement for the upcoming OGL-compatible edition of Vampire Hunter$, but it can work with any other modern game.
AMA is 100% compatible with the OGL and the SRD (edition 3.5). I dare you to find a comparable value on RPGNOW!