Magazine

Magazines are ammo storagers and feeding devices. Most of the firearms in Counter-Strike Online are fed with magazines

Type of magazines appear in CSO

 * Box magazines: Most firearms in CSO use box magazines. Box magazines can usually hold 5 to 60 bullets.
 * Drum magazines: Drum mags are only can be seen used by automatic combat shotguns, sub-machine guns and light machine guns in CSO, they have larger capacity than box magazines. Drum mags can usually hold 20 to 100 bullets.
 * Ammo Boxes / Ammo belts: Ammo boxes and ammo belts are only seen used by machine guns. They have the highest capacity than any other feeding devices exist in the game. These kinds of feeding devices usually can fed 100 rounds - 250 rounds. Although these kind of feeding devices have the highest capacity, using them will increase the weapon's reload time due to the larger volume and more complex loading.
 * Tube magazines: Tube magazines are usually used by shotguns. They are not be able to removed due to they're fixed and they are internal devices, that cause tube mag fed firearms usually require more time to reload because shooters have to insert bullets into the magazines until the weapon is full loaded. But this can make shooters to fire at any moment even though he/she hasn't finished the reloading. In game, tube mags can usually hold 7 rounds to 15 rounds.
 * Cylinders: Cylinders are only seen in revolvers. Like the tube magazines, they are fixed and can't be removed. So, to reload revolvers, shooters have to insert all the bullets to fill the cylinder or use speedloaders. Modern revolvers usually hold 6 rounds in their cylinders, although the revolvers appear in CSO can hold 7.
 * Chambers: In CSO, some weapons have no magazines, they can only hold 1 round in their chambers. Only single-shot weapons use this kind of mechanism.

Pistols:

 * Glock 18
 * H&K USP
 * SIG P228
 * Desert Eagle
 * FN Five-SeveN
 * Beretta 96
 * Infinity
 * Automag

Sub-machine guns:

 * Steyr TMP
 * MAC-10
 * MP5
 * UMP45
 * FN P90
 * K1A
 * MP7A1
 * TDI Vector
 * Skull-3
 * Tempest

Assault Rifles:

 * FAMAS F1
 * L85A2
 * Galil
 * FNC
 * AK-47
 * AKM
 * Colt M4A1
 * HK416
 * Steyr AUG A1
 * SG552
 * FN SCAR L
 * FN SCAR H
 * XM8
 * XM8 Sharpshooter
 * FN F2000
 * M14 EBR
 * M16A4
 * AN-94
 * StG 44
 * QBZ-95B
 * Lightning AR-1
 * Kart Rifle

Sniper Rifles:

 * Steyr Scout
 * AWP, R93, AW50F
 * SIG SG550 Sniper
 * HK G3SG-1
 * VSK-94
 * SVD
 * TRG-42
 * M95
 * WA2000
 * M24
 * XM2010
 * M200
 * AS50
 * Skull-5

Machine guns

 * Avalanche

Lists of firearms fed with drum magazines

 * USAS-12
 * Skull-11
 * QBB-95
 * Thompson
 * MG36

List of firearms fed with ammo boxes / ammo belts

 * M249
 * Skull-7
 * MG3
 * M134 (ammo belt only)
 * HK 23E
 * M60E4
 * MK48
 * PKM
 * M2HB

List of firearms fed with tube magazines

 * Benelli M3
 * Benelli M4
 * M1887
 * KSG-12
 * SPAS-12
 * Lightning SG-1

List of firearms with cyclinders

 * Colt Anaconda
 * Skull-1
 * Gatling

List of chamber-loaded / Muzzle-load firearms

 * Double-Barreled Shotgun
 * Quad-Barrel Shotgun
 * M79 Saw Off
 * Flintlock Pistol
 * Bazooka
 * AT4
 * AT4-CS
 * Cannon
 * M203

List of firearms / weapons with unallocable / unknown feeding devices

 * Lightning Blaster (Seems to be loaded with capsules)
 * Lightning SMG-1
 * Lightning Big-Eye
 * Crossbow
 * Wild Wing (loaded with gunpowder in baskets)
 * Salamander (loaded with nitrogen gas)