The Beretta 92FS was supposed to be the default pistol of the game, but it was replaced with the Px4 in the final build. Aiden can be seen holding one in the main menu background.
The Beretta Px4 Storm is Aiden's starting handgun. It also appears to be the sidearm of the Chicago Police Department. Maurice Vega also uses one in the assassination attempt that sets up the the events of the game. It has a magazine capacity of 10 rounds, implying it is the .45 ACP variant.
The Kimber Warrior appears as simply, "1911." The model is taken directly from Far Cry 3. Like the PX4 this holds 10 rounds, which is incorrect for this model which holds 8+1 in the chamber. A suppressed version, called the "Spec Ops 1911" is also available.
The Desert Eagle Mark XIX appears as the "D50." It has a magazine capacity of 8 rounds. A gold version can be acquired through the uPlay service. The gun is called "EMP Pistol" in the Digital Trip "Alone".
A modernized version of the Mateba Autorevolver is offered in three versions. The three versions are the "M8-M," "Chrome," and "Auto-6." They are semiautomatic, fully automatic, and burst fire respectively. All three versions feature picatinny rails above and below the barrel and custom vent holes.
The MP-412 REX appears as the "MP-412." The gun is obtained through a promotion on Monster Energy Drink's website. When the gun is broken open, no shell casings are ejected, nor does Aiden dump them out. He simply slaps the cylinder and that somehow magically reloads it. The weapon is also viewable in one of the Privacy Invasion events where a couple play Russian roulette during sex.
The OTs-33 Pernach apears as the "R-33". It incorrectly holds 30 rounds. The model is taken from Ghost Recon: Future Soldier. A fictional variant called the "R-33B" also appears in certain versions of the game. It has brown grip panels and fires in 3-round burst mode (which would be possible on the earlier OTs-23 Drotik instead). Interestingly, this is the only pistol in the game that has the hammer correctly cocked.
The SIG-Sauer P250 Compact appears as the "P-9mm." It incorrectly holds 17 rounds, which would be correct for the full size P250, not for the Compact. The gun's description incorrectly states that it was developed in Austria.
The D12 is a modern Over/Under shotgun with short barrels and an over-folding wire stock. The receiver, pistol grip, and trigger guard appear to be based on a Mossberg Maverick 88 Serbu Super Shorty.
The Mossberg 500 appears as the "SG-90". The model is taken directly from Ghost Recon: Future Soldier and holds an unrealistic 8 rounds in a 5-round magazine tube. The gun features a Knoxx COPstock and a heat shield.
The Heckler & Koch MP5N appears as the "MP5". The model is taken from Far Cry 3 for the most part, but interestingly they changed the odd rear sight of Far Cry's MP5 and put on the correct diopter sight.
Featured as the "SMG-11", as well as a suppressed "Spec Ops" variant. Both are available from weapon stores, but a free copy of the regular MAC-11 can be acquired by hacking a cTOS tower, while its "Spec Ops" variant can be acquired by completing 10 Gang Hideout assignments.
The TDI Vector appears as the "Vector .45ACP". A "Spec Ops" variant with a suppressor and a black finish is rewarded for successfully tailing 5 players online.
The AKM appears with a wooden furniture and is mis-labelled as an "AK-47". This appears to be a reworked version of the AK-103 model from Far Cry 3, with the gas block changed and the rail accessory mount removed. It still has the AK-103 stock and muzzle brake.
The Heckler & Koch HK416 appears as the "416". The gun is a mandatory purchase as an Act I mission objective. A special version called the "Wildfire", with special woodland camouflage and increased rate-of-fire, is acquired by finding all 6 Missing Persons. The in-game HK416 is modeled with the slanted magazine well of the HK416 A5, rather than the nearly horizontal magazine well of the original version.
The Heckler & Koch HK417 appears as the "417". The model is taken from Ghost Recon: Future Soldier. The rifle is incorrectly shown to fire in 3-round bursts and it has no sights whatsoever.
The same fictional "OCP-11" from Ghost Recon: Future Soldier appears in the game, although with small differences: the top rail is shorter and the trigger guard is different. This is the weakest and cheapest assault rifle in the game. Blume security guards and cops can be seen using this gun often.
The P416 appears as the "Goblin." Despite using the name of the Ghost Recon: Future Soldier P416, the actual model appears to be taken from Far Cry 3 which is a different variant of the P416. Oddly, the in game rifle has the rear sight unfolded, but the front sight is folded. A "Spec Ops" version with a suppressor and a black finish is a reward for finding 9 weapons crate.
The Remington ACR is a high-tier assault rifle available for purchase from the in-game gun stores. The Biometric Assault Rifle is available in the Signature Shot Pack. The B.A.R. has an urban camo finish and a lowered fire rate to maintain accuracy.
The Ultimax 100 Mark 3 appears as the "U100". The drum mag holds 75 rounds. This weapon cannot be bought at gun stores; it must be picked up from killed enemies. Enforcers like to carry these alongside with the AA-12.
The Barrett M107CQ appears as the "M107". A special version called "Destroyer" is available after completing 10 criminal convoys. The Destroyer variant oddly holds only 2 rounds in the magazine while the regular version holds the correct 10 rounds.
The Galil ACE 23 appears as the "AC-AR." It appears as a burst fire sniper rifle and holds 20 despite using 30 round STANAG magazines. It is missing the rail above the handguard and it is also missing the rear sight.
The SVD Dragunov appears as the "SVD." The model has the same shortened barrel as the SVD from Far Cry 3, though unlike FC3, the gun in this game is correctly modeled as a right-handed weapon, and has the later production skeletonized synthetic stock. Presumably to use the same hand positions as other rifles, the SVD's receiver is shortened to the point the trigger guard is connected to the magazine release as on a PSL Sniper Rifle; it appears the receiver is a hybrid of the ones from the Far Cry 3 SVD and the Ghost Recon: Future Soldier PSL-54C.
The scope reticle is from a Belarusian Zenit 8x42 POSP scope, with civilian 1.5m and 0.5m stadiametric rangefinder lines intended for hunting elk and deer instead of the single 1.7m human line of the PSO-1 and military POSP.
