When going to a drug deal with Hector the Toad (Al Israel), Tony Montana (Al Pacino) carries a Pietro Beretta Model 81 (with Pachmayr grips) in with him. But when the drug deal goes wrong, Hector takes the gun from Tony and uses it to threaten him, and then proceeds to put it in a suitcase with the drugs and grab his chainsaw. Tony Montana carries this same model Beretta throughout the rest of the film, which he carries in a holster in the small of his back, fixing it with a suppressor when he visits Frank Lopez. This weapon was previously misidentified at the similar Model 84 BB, but the records for the weapons sent to the production indicate that an 81 was used.
Screenwriter Oliver Stone felt that Tony's Beretta was integral to the character's image, and a specific reference to Tony's Beretta or "Baretta" (sic) appears on page 158 of the assistant property master’s working production script describing Manny’s death scene. The assistant property master circled “Baretta” (sic) in red ink to be sure that exact gun was the one to be used by Mr. Pacino in the film. The Beretta also appears briefly onscreen lying on Tony’s desk next to his enormous pile of cocaine during the climactic ending of the film. (IMFDB thanks The Golden Closet for providing the documentation on this gun.)
Beretta M951
When the drug deal with Hector the Toad goes wrong, a few Colombian thugs storm the room. One thug armed with a Beretta M951 takes Angel (Pepe Serna) into the bathroom at gun point, and also forces Tony Montana (Al Pacino) to watch as his friend is cut up with a chainsaw. A few minutes later when Manny (Steven Bauer), and Chi Chi (Ángel Salazar) come into the room to save Tony, Tony takes the gun from the thug and kills him with it, and then uses it to kill Hector in the street. Manny later uses a suppressed Beretta M951 to kill Frank Lopez (Robert Loggia).
MAC-10
During the chainsaw scene, some of the Colombian thugs including Marta (Barbra Perez) wield suppressed MAC-10s. Manny (Steven Bauer) also uses a MAC-10 when coming to rescue Tony. The two hitmen at the Babylon Club also use MAC-10s, as well as some of Sosa's men during the finale.
Colt Python
When Manny and Chi Chi (Ángel Salazar) come to rescue Tony from being chainsawed, Chi Chi uses a Colt Python to put a bullet into the chest of one of the Columbian thugs. One of Tony's (Al Pacino) men uses a Colt Python at the end of the film, before being killed by Sosa's men.
Uzi
One of the guards in Sosa's (Paul Shenar) cocaine factory has an Uzi. Many of the men Sosa sends to kill Tony Montana are armed with Uzis as well. Tony takes one from the assassin that shot his sister and uses it against him. Chi Chi (Ángel Salazar) also can be seen using an Uzi during the final battle scene. A few Uzis can also be seen in the display case in which Tony retrieves his M16.
Smith & Wesson Model 36
The undercover cops led by "Seidelbaum" (Ted Beniades) that arrest Tony Montana for tax evasion are armed with Smith & Wesson Model 36 snubnoses. Gina Montana (Mary Elizabeth Mastrantonio) later shoots a Model 36 at Tony when confronting him in his office. Mel Bernstein (Harris Yulin) has a Model 36 in his holster when he is shot by Tony. Tony Montana (Al Pacino) also carries a Model 36 in a shoulder holster throughout the film.
One of Sosa's men uses a Remington 870 shotgun with a pistol grip at the end of the film.
FN FAL
One of the men Sosa sends to kill Tony can be seen holding an FN FAL battle rifle while going up the stairs to Tony's room.
Heckler & Koch HK33
The collapsable stock variant of a Heckler & Koch HK33 can be seen hanging in the case where Tony pulls his M16 from.
Valmet M82A
Hanging next to Tony's H&K HK33 in the gun case is a Valmet M82A bullpup rifle.
Colt AR-15 with Fake M203 grenade launcher (a.k.a. "My Little Friend")
Tony Montana (Al Pacino) uses a Colt AR-15 with a Fake M203 grenade launcher attached during the final battle. In one of the film's more memorable moments Tony yells out "Say hello to my little friend!" and blows a door down with a 40mm grenade, killing several of Sosa's men. Also of note is that he has two magazines taped together 'jungle style'. After expending his first two magazines, he inserts a single 30 round before the end. The grenade launcher used is a 39mm smooth bore "Fake M203" used to imitate the M203 in the 1980s before the advent of the Cobray CM203 Flare Launcher, and is also used in films such as Predator and Heartbreak Ridge. The Fake M203 grenade launcher was custom made for use on the film and the firing pin has been removed to prevent the use of live rounds. The launcher was fabricated because the property master was unable to locate any live firing grenade launchers for production. He had this M203 grenade launcher hand crafted (not molded) by the studio prop department. The launcher was created with an extra large trigger guard and wider ribbing on the barrels than are found on the traditional M203 design. Originally an M16A1 was used with the grenade launcher and the AR-15 was substituted after cinematographer John Alonzo determined that the AR-15’s firing sequence could be timed to synchronize with the Arriflex cameras, which would result in elongating the duration of muzzle flashes seen on film.
TRIVIA: Not only is the launcher used in this movie the same type used in Predator, but the particular launcher used in Scarface is the exact same launcher used in Predator. (IMFDB thanks The Golden Closet for providing the documentation on this gun; also see their sales page for the launcher with non-firing replica Colt AR-15 at this link.)
M16A1
Some of Sosa's assassins sent to kill Tony carry M16A1 assault rifles.
Spanish Zabala Sawed-off Double-barreled Shotgun
The Skull (Geno Silva) uses a 12 Gauge Double Barreled Shotgun, known in the Latin world as 'Lupara', to kill Tony Montana. It was a 12 gauge side-by-side double barreled shotgun manufactured by Zabala Hermanos, S.A. that had its stock cut down. (IMFDB thanks The Golden Closet for providing the documentation on this gun; also see their sales page to view more information on the actual screen used Zabala shotgun, here).