The Desert Eagle is referred to as the "Falcon 357" and is the first firearm acquired by Jack Carver. It holds 9 rounds and is the only pistol in the game.
FN P90 Submachine Gun
The FN P90 is featured as the "P90 SMG." It's a loud but potent weapon which is effective at short range, at least until the Jackhammer becomes available and largely makes it obsolete. Something terrible appears to have happened to the front grip.
Heckler & Koch MP5SD3 Submachine Gun
The MP5SD3 is presented as the "MP5 SMG" in game, and is the only silenced weapon available.
Colt M4A1 Carbine
The M4A1 Carbine is the second weapon Jack acquires, and is called the "M4 Assault Weapon" in game. It's a reasonably potent weapon, though outclassed by later assault rifles as it lacks a scope or grenade launcher.
Heckler & Koch G36K Assault Rifle with AG36 Grenade Launcher
The XM29 OICW is present as the "OICW," shown as a 5.56mm rifle with a fixed 3x magnification scope and repeating grenade launcher. The grenades travel in a much longer arc than those of the AG36, but are otherwise unremarkable; the complex HEAB functionality is not represented in-game.
M249 Squad Automatic Weapon
Pancor Jackhammer Automatic Shotgun
The Pancor Jackhammer is featured in game as the "Jackhammer Shotgun," the only such weapon in the game.
Accuracy International AW50F
The Accuracy International AW50F [identified by the distinctive Madco barrel] is present as the "Sniper Rifle." It features a precision optic scope with a built-in rangefinder and variable magnification; 3x, 6x, 12x and 18x.
Rocket Launcher
A fictional rocket launcher is used in-game, possibly extremely loosely based on the M202 FLASH multi-shot rocket launcher; the Far Cry launcher, however, has a single common exhaust for all four tubes, and reloads using a four-rocket magazine located at the weapon's midpoint.
General Electric M134 Minigun
The GE M134 Minigun is seen mounted in fixed positions and on Krieger's helicopters. It replicates the grip of the minigun from Terminator 2: it's not clear precisely why, since it's never carried by anyone in-game.
Browning M2
Browning M2 heavy machine guns are seen mounted on various vehicles throughout the game, and can be controlled by Jack when he is using them. They have limited ammunition supplies, but do not overheat as in many other games.
Mark 19 Grenade Launcher
The Mk 19 grenade launcher is depicted in-game as a mounted weapon called the "Mortar." The weapon is one of the least accurate to its real-life counterpart, depicted as an extremely slow-firing single-shot gun with a built-in rangefinder and trajectory calculation system.