Colonel John 'Hannibal' Smith (Liam Neeson) carries an unknown 1911 (possibly a Colt XSE, or some Kimber variant).
It was definitely a Para-Ordnance model .45, you can see it has a wider grip, his mags are double stacked, and the logo is on the right side of the slide. - Gunmaster45
Colt Anaconda
A corrupt police officer working for General Tuco (Yul Vasquez) brandishes a Colt Anaconda revolver in the film's prologue.
Smith & Wesson Model 28
One of General Tuco's men is briefly shown firing a Smith & Wesson Model 28 revolver in the film's prologue.
Beretta 92FS
Various U.S Army soldiers use Beretta 92FS pistols during the film, including members of Lt. Sosa's DCIS team. A CIA agent attempts to use a suppressed Beretta on Pike (Bryan Bloom) in Frankfurt, Germany. Pike (Brian Bloom) also has a Beretta 92FS in a tactical vest at the shootout in the harbor in the climax.
Beretta Px4 Storm
It seems that B.A. Baracus' (Quinton "Rampage" Jackson) sidearm throughout the whole film is a Beretta Px4 Storm.
Pike (Bryan Bloom) uses a SIG-Sauer P226 pistol when he kills the rest of his Black Forest guys in Baghdad, and in Frankfurt while pursuing the A-Team. Lynch (Patrick Wilson) also carries a P226 throughout the film, and is seen pulling it on Pike in the car in Frankfurt.
A guard in the prologue is seen with a Franchi PA3 shotgun.
Remington 870
A Remington 870 are seen in the hands of General Tuco's men, and also is used by an U.S Army MP during the escape of Sgt. Bosco "B.A." Baracus (Quinton Jackson).
Submachine Guns
Heckler & Koch MP5A3
CIA agents and U.S Army soldiers both use MP5A3 submachine guns during the film's finale.
A guard at the bank during the the exchange of the printing plates carries an MP7 submachine gun. It is hard to see due to being a black gun held in front of a black trench coat.
Rifles
Ruger Mini 14 Stainless version with Folding stock
The classic Ruger Mini-14 with a factory folding stock in Stainless steel is used by Hannibal in Mexico to rescue Face. This is most likely a tribute to the original TV show, in which the Mini-14 was the favorite weapon of the A-Team.
Heckler & Koch HK33
One of General Tuco's soldiers is briefly seen with a scoped HK33 while searching for the A-Team.
Heckler & Koch G3A3
Several of General Tuco's men use Heckler & Koch G3A3 rifles when pursuing the A-Team in Mexico.
M4A1 Carbine
Col. John 'Hannibal' Smith (Liam Neeson) and Lt. Templeton 'Faceman' Peck (Bradley Cooper) are both seen using M4A1 Carbines with tan furniture, Magpul CTR stocks and red dot sights during their final mission in Baghdad. Face also wields an M4A1 in the harbor shootout in the climax.
M16A2
Several U.S Army soldiers in Iraq are seen with M16A2 rifles.
AKM
Iraqi guards escorting a valuable cargo in Baghdad are armed with AKM rifles.
M1 Garand
An U.S Army honor guard is shown firing M1 Garand rifles at a funeral.
SIG SG 552
Pike(Brian Bloom) carries a SIG SG 552 with a foregrip while pursuing the A-Team in Frankfurt.
Heckler & Koch G36K
Pike(Brian Bloom) uses a Heckler & Koch G36K fitted with rails and a foregrip during the film's finale. They are also carried by Black Forrest contractors in Iraq.