The prison guards, U.S. Marshals and DEA agents arm themselves with SIG-Sauer P226 handguns. The convicts use several P226s captured from the guards, most notably Cyrus "The Virus" Grissom (John Malkovich), who steals the co-pilot's SIG-Sauer from him after he removed it from the lock box and uses it for much of the film.
Remington 870
Prison guards carry Remington 870s when the cons are being loaded onto the plane. Several 870s are also included in the arsenal located in the belly of the aircraft and are later broken out by the convicts.
M16A2
The cons take several M16A2 assault rifles from the weapons stash. The rifles fire fully-automatic, which means that they are actually M16A2 upper receivers placed on full-auto lower M16A1 receivers, typical of all Hollywood "M16A2" rifles.
Rubber M16 prop
When Cyrus throws down his empty M16A2, it changes to a rubber prop featuring the M16A1 style sights and lacking a forward assist, shell deflector, and magazine fencing. This means that the prop was mostly likely cast from a civilian AR15 Sporter-1 rifle fitted with A2-style handguards.
M16A1 (With A2 handguards)
The National Guardsmen and some of the prison guards are armed with M16A1 rifles fitted with M16A2 handguards.
Skorpion SA
A cartel member (Eddie Pérez) duel wields two guns, one being a Skorpion SA, the other being...
Beretta 92SB
A Beretta 92SB pistol is seen held by a cartel member, noted by its rounded trigger guard.
Seecamp LWS-32
The undercover DEA agent Willie Sims (José Zuñiga) is given a Seecamp LWS-32 .32 ACP pistol, which he draws before being killed by Cyrus.
Glock 17
U.S Marshal Vince Larkin (John Cusack) uses a Glock 17 2nd generation as his issued sidearm.
Defense Technologies 1315 37mm
When Cyrus (John Malkovich) takes the guns out of the weapons hold, a few of the cons use Def Tech 1315 37mm launchers, used to look like HE launchers.
Colt Woodsman "Assassin" Model
One of the cartel members (Thomas Rosales Jr.) uses a Colt Woodsman with both a modified slide and barrel to thread a suppressor, commonly known as the "Assassin" model. Cameron Poe (Nicolas Cage) comments that the cons would hear the shot, so he threads a suppressor on it. When Poe dispatches all the cartel members, he takes the gun for his own use, before dropping it diving from an explosion.