"Guns, Guns, Guns" by Greg Porter,
Published and distributed by BTRC.
ISBN = 0-943891-19-1 BTRC # 4001
3G3, as it is affectionately known to its fans, provides weapon and ammo statistics for role playing games such as CORPS (Greg Porter's own game), Cyberpunk 2020, GURPS, Hero, Traveller, Time Lords, Torg, and Twilight 2000. In its about 136 pages lie hundreds or even thousands of firearms and ammo. Remember, this is =far= before the advent of the Open Gaming Licence.
It starts with a section on basic terminology, and moves from that beginning to a section on conventional weapons. This is the meat-and-potatoes for people wanting to use this book's highly accurate statistics for running games other than the ones included. Fade that into a section on Lasers, followed by sections on: Particle Beams, Railguns, and melee weapons.
Then starts the games sections with conversions to: Time Lords, CORPS, GURPS, Master Book, Hero, two flavors of Traveller, Cyberpunk 2020, Battlelords of the 23rd Century, Nexus, and Heavy Gear.
Although it has no table of contents, the index is good. In the back of the book are charts for ammunition, and design sheets for several types of weapons and ammo.
Although this does not include ay D20 Modern conversions, the info on the weapons and ammunition are easily converted into almost any game system. I would recommend this book (even now!) to GM's who want to add more than a dash of realism to their modern campaigns.