The FN FNP-45 Tactical, called the "FNX45" in game, is one of the .45 semi-automatic handguns in the game. It uses 15 round .45 ACP magazines, and accepts a red-dot sight as well as pistol flashlight. The model appears to be a redone version of the "4-Five .45" taken from ArmA 3, as it even sports the same attachments. The weapon and it's magazines currently only spawn at US Helicopter wrecks, making it one of the rarer sidearms available to players.
AWC Amphibian S Ruger MKII
The AWC Amphibian S Ruger MKII appears ingame as the "Amphibia S", using a standard 10-round .22LR magazine. It is incredibly quiet, being almost undetectable by players beyond very close range. It is intriguing that a very expensive variant of a pistol used by U.S. Navy SEALs appears in the game at all. Like the FNX45, it spawns at US Helicopter Crashsites, however it's magazines can be found at regular wrecks and other military locations.
CZ 75 SP-01 SHADOW
The CZ 75 SP-01 SHADOW appears, known in-game as the "CR75", and is made by "Cheraruska Zbrojovka", an odd spin on the real world CZ company. Like the FNX-45, it accepts the ambiguous "pistol suppressor" (also incorrectly used on the .45 ACP FNP-45) and "pistol flashlight" (that is also used by the FNP-45 and both 1911 variants).
Kimber Warrior
A slightly-modified Kimber Warrior appears ingame as the "1911". Unlike the real Kimber Warrior, the in-game 1911 has a traditional M1911-styled rear sight, and has straight slide serrations rather than angled ones. It takes standard 7-round magazines and can sport a pistol flashlight, due to its rails.
A much rarer engraved variant of the 1911, accurately called the "1911 Engraved", is available as well.
Walther P1
A Walther P1 appears as the "P1", and uses 8 round 9x19mm magazines. It can only accept pistol suppressor attachments. It is relatively uncommon in comparison to the Makarov and CR-75.
Thompson Center Arms Contender
A Thompson Center Arms Contender appears as the "LongHorn". The in-game Contender previously had a permanently attached scope until patch 0.57 where the Scope could be detached and placed on the Crossbow. It always spawned with the Scope Attached and could mount a Crossbow Holosight as a close range alternative. It uses .308 Winchester ammunition.
Makarov IJ-70
The Makarov IJ-70 appears as the "Makarov IJ70", and is chambered in .380 Auto. It can accept only pistol suppressor attachments.
Mauser C96 Red 9
The Mauser C96 Red 9 appears as the "Red 9", and is chambered in 9x19mm. Currently, it is the only pistol that can accept buttstock attachments.
Remington 1866 Derringer
A Remington 1866 Derringer appears as the "Derringer", and is chambered in .45 ACP rounds. Unlike most of the other pistols, it cannot accept attachments. It comes in 3 varieties; Black, Grey and a stylish Pink.
Orion Flare Gun
An Orion Flare Gun was added to the loot tables in 0.53. While the weapon and it's ammunition currently spawn at paddleboat spawns, it can spawn in any weapon location in Residential or Military Locations. Despite it's description of not being used as a weapon, it makes an ideal last resort against an unsepecting player. It's ammunition is currently bugged where Ejected unfired rounds cannot be reused.
Revolvers
Colt Python
A chrome Colt Python, known as the "Magnum" in-game, appears as (currently) the only revolver in the game. The Colt Python is correctly chambered in .357 Magnum, and accepts a speedloader for faster reloading.
Shotguns
Baikal IZH-43
The Baikal IZH-43 appears as the "IZH-43", and uses 12 gauge shells. A Sawed-Off IZH-43 can be created using a hacksaw, increasing the recoil and decreasing accuracy but taking up less inventory space. It can be loaded with twin-shell speedloaders.
Baikal MP-133
The Baikal MP-133 appears as the "MP-133 Shotgun", using a 6-round 12 gauge tube. Another variant with pistol grips and a shorter barrel appears as the (rather long-named) "MP-133 Shotgun with pistol grip", holding 4-rounds instead of the standard variant's 6.
Rifles
M4A1 Carbine
The M4A1 Carbine appears, being the only select-fire weapon as of yet. It is correctly chambered in 5.56x45mm ammo, and features the widest amount of customization available to any weapon (Accepting everything from black and OD Magpul stocks and handgrips, to Aimpoint M68 CompM2 and ACOG sights, as well as bipods and flashlights.) It also has the largest variety of magazines; being the standard 30-round STANAGS, as well as 10, 20, 30 and 40 round Magpul P-Mags (All in fashionable black and fabulous OD green) and two coupled 30 round STANAG mags. As per text on the M4A1's receiver, the rifles in game are manufactured by CMMG Provisions, a company long associated with Bohemia Interactive, who was also responsible for designing the "MX" series appearing in ArmA 3.
Mosin Nagant M91/30
The Mosin Nagant M91/30 appears as the "Mosin 9130". In the early days of DayZ development, the weapon incorrectly uses 7.62x51mm ammo but this was rectified as of 0.55 and the Mosin will now fire the correct 7.62x54mmR. The Mosin-Nagant M91/30 can be equipped with a few attachments, including an M44 Compensator, M91 bayonet, and PU scope. In previous versions a 12x Scope could be attached however this has recently been changed so that only the PU Scope can be attached. The Mosin-Nagant can be spray painted black, green, or a camouflage mix of both. Since of 0.57, the Long Range Scope has been deleted and now the only optic for the Mosin is the PU scope.
As of the 0.48 update, the "Mosin 9130" can be cut down into an Obrez, called the "Sawed-Off Mosin 9130" ingame. Similar to the Sawed-Off IZH-43, the Obrez Mosin features saw marks on the barrel and stock, where the rifle has been cut.
SKS
A Yugoslavian SKS M59/66 appears, simply, as the "SKS". It is correctly chambered in 7.62x39mm, and accepts a bayonet as well as PU scope. The SKS, like the Mosin-Nagant, can be spray painted either black, green, or a camouflage mix of the two.
AKM
An AKM rifle appears as the "AKM". It uses 7.62x39mm ammunition, and is compatible with many attachments. Among them are a PSO-1 scope, several handguard replacements, and an interchangeable full-wooden and folding stock (which is not possible in real-life, as a full-stock AKM receiver does not have the necessary modifications to sport a folding stock.) The game's AKM can become an AKMS that is created when the AKM is given a folding stock. Despite the stocks not being interchangeable in real life, the AKM retains its name and the difference is completely aesthetic.
AK-101
An AK-101 appears in-game chambered in 5,56x45mm NATO. It uses its own 5,56mm AK-101 magazines and can only use the bipod and weapon flashlight when the RIS rail handguard is equipped. It can also mount most of the AKM, AK-74 and AKS-74U style stocks in addition to the PSO-1 Scope.
Despite its look it's actually a modified model of the AK-74M, an older model seen in DayZ's development cycle before the AK-74 was officially added. It's located in general military loot, although its ammunition is comparatively rarer than the native 5,45x39mm and the 7,62x39mm.
AK-74
An AK-74 appears as the "AK74", and uses 5.45mm ammunition. It can mount a bipod and weapon flashlight when the AK Handguard Rail is attached and can fit the PSO-1 Scope.
AKS-74u
The AKS-74U appears in the game, commonly spawning in military zones. It's chambered for 5.45x39mm. Unlike its bigger brother the AK74, the AKS-74U is incapable of mounting any handguards or the PSO-1 Optic. However, it's small compact size means it can be stowed away inside some of the larger backpacks, making it the ideal backup weapon to a Sniper.
Steyr AUG A1
The Steyr AUG A1 appears as the "Steyr AUG Automatic Rifle", and is chambered in 5.56mm. Added in 0.51, the Steyr AUG is one of the rarer weapons that spawns at US Helicopter Crash Sites. It features it's unique 1.5x Swarovski Optik. It can take it's own 30 round Steyr AUG Magazines as well as STANAG, both using 5.56mm. However with the 0.57 update, the M4 attachments (counts as magazines even) are extreamly rare and finding attachments for the AUG is considered very hard.
Ruger 10/22
The Ruger 10/22 is featured, as the "Sporter 22" and manufactured by "Kruger Arms" (a common spin on Ruger-based firearms for copyright issues). It can utilize either the standard 10 round rotary magazine or use a 30 round aftermarket magazine, and is chambered in .22LR. The 0.57 patch added the ability to mount a x8 Hunting Scope.
Winchester Model 70
The Winchester Model 70 appears in the game, and is chambered in .308 Winchester ammunition. Before 0.57, this weapon was incorrectly labeled as the "Winchester Model 70 Alaskan" before later corrected in game, as the Alaskan variant does not offer .308 Winchester. It can be mounted with a x8 Hunting Scope.
Blaser B95 "Luxor"
The Blaser B95 "Luxor" appears as the "Blaze 95 Double Rifle", chambered in .308 Winchester (Which is one of many calibers the B95 supports). It has a measly two round capacity, but is very accurate even out to 200m. An option to fire both barrels exists by pressing "T" which will fire both barrels in quick succession. The 0.57 patch added the ability to add a Hunting Scope with a x8 magnification.
Winchester Model 1892
A Winchester Model 1892 appears as the "Repeater", and is chambered in .357 Magnum with a internal capacity of 11 rounds. Currently, it is the only lever-action rifle available in the game.
Baikal IZH-18MH
The IZH-18MH appears as the "IZH-18 Rifle", and is chambered in 7.62x39mm rounds. Currently, it is the only break-action rifle available in the game. Along with the Mosin 9130 and the IZH-43, it can be modified into a sawed-off variant, resulting in incredibly reduced effective range and much higher recoil, however it can be concealed easier and can be stored inside backpacks and other storage containers.
FN Trombone
The FN Trombone appears as the "Trumpet" in-game, and is chambered in .22LR. Compared to the Ruger 10/22, it does not require a magazine, however it trades rate of fire and modularity for accuracy and simplicity. It can also be disassembled into a more compact form, allowing it to be stored inside a backpack. Currently, like some other weapons, it's able to accept an improvised suppressor. As of 0.57, this weapon accepts the attachment of a x7 hunting scope.
CZ-527 Carbine
The CZ-527, 7.62x39mm carbine variant, appears as the "CR527 Carbine", manufactured by "Cheraruska Zbrojovka" as the CR75 is. The original model created was the .223 variant, but this was later changed to accommodate gameplay. As of 0.57 it accepts the attachment of a hunting scope.
Dragunov SVD
The Dragunov SVD appears as the "SVD", and is correctly chambered in 7.62x54mmR ammunition. Added in 0.57, the SVD is one of the very first military sniper rifles added to DayZ, besides the experimental VSS (currently is not for use). It spawns in only Russian Helicopter Crash Sites (Mi-8s), and it uses it's own SVD 10 round mags. The mags spawn in general military locations.
Submachine Guns
Heckler & Koch MP5K
The MP5K appears as the "MP5-K". Although it is found with a PDW-Style stock by default, it does not have the MP5K-PDW styled flash hider and is thus a standard MP5K with the stock attached. The MP5K can also attach a Pistol Suppressor and a Compensator, turning it into an MP5K PDW.
Heckler & Koch UMP
The Heckler & Koch UMP appears as the "UMP45", and is chambered in .45 ACP rounds. The UMP45 has the most stopping power of any secondary gun 1 shotting players to the chest, and can be found in helicopter crash sites and military tents. It can attach a pistol suppressor and the RV1 RDS, M68, and Acog optics.
PM-73 RAK
The PM-73 RAK appears as the "PM73 RAK". The PM-73 is a .380 Auto variant of the PM-63, which was included as the developers decided against adding 9x18mm ammunition. It's reputation as one of the game's most rare weapons was rectified with an update that implemented Central Loot Economy. It commonly spawns at police stations and tank wrecks and can take either 15 round or 25 round magazines.
Grenades
Currently, grenades only spawn at helicopter crashsites, however the RGD-5 has a tendancy to spawn at Military Locations at an extremely low chance. They are extremely rare, and are unlikely to be encountered, even by experienced players.
M67 Hand Grenade
An M67 Hand Grenade appears as the "Explosive Grenade". The in-game M67 has an unusually large explosion, more akin to high-level aircraft ordnance, rather than a hand grenade. This is a result of the explosion effect for grenades not being finished, and re-using the explosion of a gas station instead. These Grenades, while extremely rare can only be found at US Helicopter Crash Sites.
M84 Stun Grenade
The M84 stun grenade appears in DayZ as the "Flashbang". Contrasting the regular M67 grenade, the M84 has a very long description explaining it, whereas the M67's simply says "Grenade". Unlike the M67, the Flashbang can be found at various Military Wrecks such as Jeeps, Police Cars and Helicopter Crash Sites, at one point in development Flashbangs would also spawn in Police Stations.
RGD-5 Hand Grenade
The RGD-5 hand grenade appears as the "RDG-5 Explosive Grenade". The RGD-5 is slightly more common than the M67 (though still extremely rare), and has a much shorter fuse. It is freqeuntly (although still relatively rare) found inside UAZ Jeep Wrecks and BMP and BTR Wrecks.