The silenced Colt XSE 1911 is the lvl 2 pistol, Stainless steel in game. It is found in Florida and it holds 7 rounds.
Luger P08
The Luger P08. This weapon is called the Pistol Lv.1. This is the 1st weapon you use in the game. This weapon is used by Dominic to guide Michael, Fredo and Aldo out of Havana.
Revolver
Smith & Wesson Model 27
The Smith & Wesson Model 27. This weapon is called the .357 Magnum in the game. It is a very powerful weapon killing people in either one or two shots. It has a black finish. Used by Aldo in Cuba to escort Michael and Fredo. When he is killed Dominic takes the gun. When you're back at New York you have it. Level 1 magnum.
Smith & Wesson Model 29 Nickel
The Smith & Wesson Model 29. The lvl 2 magnum, called ".44 Magnum Force" in the game, possibly a reference to the Dirty Harry film on the same name. It is found in New York, it holds 6 rounds and it is extremely powerful.
Submachine Guns
M1928A1 Thompson
The M1928A1 Thompson is used in the game by almost everybody in the game including your family. In game it holds 40 shots but it has a 50-round drum magazine. It is called the Tommy Gun in game. It is the level 1 gun of its type first seen in Cuba used by the military.
MP40
The MP40. The lvl 2 Automatic, called "MP38" in the game. Used by Dominic's men if they have the right license, and by other families, but only their high ranked men. Found in Florida. It holds an incorrect 50 rounds.
Shotguns
Double barrel Sawn off Shotgun
The Double barrel Sawn off Shotgun. The level 2 shotgun is a Sawn off Double Barrel Shotgun of unknown make and model. It holds like it should 2 rounds. It is found in the Corleone Compound it can be obtained at the beginning, easily replacing the level 1 shotgun.
Winchester Model 1912
The Winchester Model 1912. This weapon is used by almost everybody in the game. It is the level 1 shotgun it holds only one round.
Rifles
Galil Sniper Rifle
The Galil Sniper Rifle. Level 2 sniper rifle, can be found in Florida. It holds 5 rounds and is called the "Spitzer Centerfire".
Winchester Model 70
The Winchester Model 70. This weapon is used as the sniper rifle of almost everybody in the game. It is also used by a Cuban to kill Aldo Trapani in Cuba at the beginning of the game. It is also used by Dominic when he attempts to kill Fidel Castro. It holds only one round and it takes a long time to reload. Level 1 sniper rifle.
Others
Beretta 951 silenced
This is the lvl 3 pistol. Incorrectly called the "Delta M1911". It is found in Florida, it appears to have a silencer and it holds 8 rounds.
Browning Auto-5/ Remington M11
This is the lvl 3 shotgun, it is found in Florida it holds 5 rounds, used by Dominic, his men with expert gun license and high ranked enemies like Don Granado.
AK-47
The AK-47 is the level 3 machine gun, has a 60 round drum and you can carry 300 bullets, it also appears to have some type of peephole sight in game. Found in Cuba. It is used by the hitman who drives by Dominic's house in Florida. Used by high ranked people, it requires expert gun License.
SV-99
Level 3 sniper rifle, found in Cuba. In real life it holds 5 rounds, but in the game it holds 6 rounds. It is used by Dominic, his men if they have the license, and few high ranked enemies.