Overpowered (Term)

An Overpowered Weapon (OP) is something that belongs to an unofficial weapon type, often featured in many different gaming genres (especially First Person Shooters). These weapons are considered to be more advanced than any other weapon in its class (statistically or advantage-wise).

Overpowered weapons are the complete opposite of Underpowered Weapons.

Disclaimer
In Combat Arms (or in any other game, for that matter), any weapon can be "overpowered" in the right hands. There is no single perfect weapon; and even the so-called "weakest" weapons in the game have the potential to be lethal, as long as they're in the right hands.

"Overpoweredness" is a perception of the mind. Assuming you are often killed by players who wield a MAC-10, you might find that weapon to be largely overpowered. Upon picking up the weapon and trying to use it yourself, however, you realize that it doesn't perform that great for you; leaving you to wonder how the other person can be so skilled with it (if they're not a hacker).

Nonetheless, even in Combat Arms, there are a handful of weapons that are considered "OP;" only because they seem to give a much larger advantage to a player who wields one.

Unofficial List
As mentioned above, ANY weapon can seem overpowered in the right hands. Yet the following weapons are, by a majority, still generally considered as OP overall.

Weapons that don't actually Exist

 * The M419 Combat CQB SE CAMO Black MOD LE for its perfect accuracy, damage, rate of fire, portability and lack of recoil. A truly OP weapon.
 * The M4A1 Devgru, said to be far greater than the SOPMOD in CA, for its undefined statistics.

Assault Rifles

 * The G36 series for the overwhelming combination of heavy firepower, accuracy, and a practical sniper-like scope with the exception of the G36C; far surpassing most other Assault Rifles. The Autumn G36E Valkyrie, apart of the G36E Family has 20 rounds more than most other assault rifles.
 * The M416 family for its once (almost) non-existent recoil, high fire rate, and decent damage.
 * The SG556 MARK II, which outclasses every other gun in its family (even the NX-Rare SG556 CAMO). It has the highest accuracy out of any assult rifle, strong 4-hit kill, low recoil and spread and goes well with any modification.
 * The AK-74M for its strong 3-hit kill, high accuracy and controllable recoil. (Baxstar approved)

Sniper Rifles

 * The SR-25 series for being highly-accurate, powerful, and rapid-fire snipers.
 * The DSR-1 Tactical, one of the first OP sniper rifles, due to its OHKO capabilities, fast fire-rate, high portability, and 100% accuracy; previously a trait only the M24 and SPR had.
 * The WA2000 for a highly-accurate, silenced, semi-automatic OHKO capabilities.
 * The WA2000-1 Tactical, which combines the traits of the two above weapons (excluding the suppressor), enhancing its capabilities as a semi-automatic OHKO weapon with near-perfect accuracy.
 * The S 58 Musket for having the same stats as the TPG-1 Master with what is arguably the clearest and most precise scope in the game.
 * The TPG series' OHKO capabilities, combined with near-perfect accuracy, very light portability, and fast fire-rates.
 * The TRG series for being a full upgrade TPG series, improving on its weaknesses.
 * 1) The TRG-SE for its extremely high accuracy, exceedingly fast firing speed (for an OHK sniper), 10 round magazine, and double zoom scope.
 * The M99-II for its fully automatic OHKO ability and its 99 accuracy rating.
 * The MSR for its portability, having the highest out of any sniper rifle at a whopping 50, integrated supressor, exremely fast scope-in time, very good accuracy at 98 and its extremely large amount of ammunition, at 5/35 which is unheard of among OHK sniper rifles and ties with many semi/fully automatic sniper rifles.

Sub-Machine Guns

 * The P90 series for their fast fire rate, steady damage, and large magazine size.
 * The UMP family for its high ammo capacity, decent fire rate, and excellent damage for a Submachine Gun.
 * The PP-19 family for its ridiculously high Magazine size, steady fire rate, and decent power.
 * The TMP for its high damage, integrated supressor and iTech scope.
 * The T-2 for its extremely high rate of fire, damage, low recoil, and respectable accuracy.
 * The VB BERAPI LB02 for its very high rate of fire, very fast reload even with an Extended Magazine II, extremely high portability, lighter than the default M9, tight spread and easily controllable recoil pattern.

Machine Guns

 * The MK.48 MOD series for the highest damage of any fully automatic weapon in the game, a steady fire rate, a  built-in scope, all-around decent statistics, and the fact that it can be used in almost any situation; CQB or long-distance, as a mob weapon or even as a makeshift sniper rifle.
 * The RPK-74M, for its near-pefect statistics; very high accuracy (for an MG), solid damage, steady rate of fire, lack of recoil, and overall performance. Often claimed to be the single-best MG in the game in terms of effectiveness.
 * The MG36, as a member of the G36 family; for its scope, fast reload, and accurate and powerful fire.

Shotguns

 * The M4 Super 90 due to its high rate of fire for a Shotgun, high damage, relatively silent shots, low recoil, reload speed, and portability (Although the Super 90 might only seem overpowered because almost every other shotgun is "underpowered").
 * The PANCOR Jackhammer for its fire rate and large amount of damage.
 * The M590 CQB (Mariners) for its tremoundous 92 damage per shot, making it the most capable of a two shot kill, even at mid ranges. Also capable of a one shot kill to the back.
 * The AA-12 series for their extreme rate of fire, 20 round magazine, and tight spread.

Pistols

 * While not necessarily overpowered, the G23 series is known for its clean action, smooth firing speed, and effective damage; a trait most other handguns lack. Can easily replace a primary weapon.
 * The G18 for being the first pistol with a burst-fire mode, as well as the stats retained from the original G23 model.
 * The G18 Cobra for being the first fully  automatic pistol in the game.
 * The USP Tactical and USP Tactical SE for their damage, fire rate, and most importantly, their accuracy. The accuracy the USP Tacticals have makes these weapons extremely effective.
 * The 44Rem Rev for its 2-Hit kill, fast reload and fast rate of fire.
 * The C1851N for having a fast fire rate for a revolver, high portability and accuracy, a 2 to 3 shot kill, and much more ammo in reserve compared to other pistols.
 * Its NX-Forged variant, M1849 Pocket Revolver, futher improves upon it's stats and adds another six rounds to an already high ammo reserve for a Power Pistol.
 * The Beretta 93R for its high fire rate and an abnormally large magazine size, the same size as the SG550 - a fully automatic weapon.
 * The P99 for having an obscenely low muzzle climb, slightly higher-than-average magazine size, fairly high portability and fairly decent medium-long range accuracy.

Melee Weapons

 * The Tracker Knife for its extreme lightness, attack speed, and overwhelming damage.
 * The Dom Pedro Sword for its extreme length, relatively quick attack rate, and raw power; making it very efficient for shifting.
 * The Tiger Strider for its fast attack speed and severe damage rate, and the ability to OHK with an attack to the back.

Explosives

 * The M32 Grenade Launcher because of its twelve rounds of explosive, 2HKO grenades.
 * The Remote Grenade because of its ability to hide behind corners, unseen by the approaching target, and the ability to kill with it's long range explosion and it's ability where it tops the Claymore, by having a full 360 blast radius.

Other

 * Almost any Specialist weapon; since only Specialists have the "authorization" to use them.
 * Especially the Auto-Turret for its ability to lock-onto nearby enemies and fire automatically, sheer durability and ability to be concealed behind corners and in tight areas that players cannot enter.