The K-SMG, is an SMG rifle with a moderately high rate of fire. Like the Machine Gun, the K-SMG can be dual-wielded. It can also have a grenade attached to the muzzle, which it will fire off like a rocket. When in grenade attachment mode, only one K-SMG can be held.
The primary fire is very powerful, and very accurate (save the natural movement of the character's hands), especially when compared to the Machine Gun. The reload time for primary fire mode is also fairly short.
The muzzle flash on this gun is easily the largest in the game, taking up more than half the screen. When it's being dual-wielded it can be hard to see when firing.
The secondary firing mode (grenade attachment) is an explosive; a direct hit will kill an enemy. The grenade doesn't have an arching fire like that of the rifle mounted grenade launchers of that time (and this time for the most part), though the grenade could simply be a rocket ignited by a blank round or possibly even electrical charge. However, the ammo capacity is extremely low and it takes a while to reload the weapon. In Mapmaker maps, the secondary firing mode is not available if the map is played in Story mode.
The K-SMG only appears in TimeSplitters Future Perfect, with its first story appearance being in Scotland the Brave. According to Anya, the weapon is not on record for the time period and therefore must have been custom built for Crow's army. It appears to have a gas port that looks similar to that of the Kalashnikov series of rifles, so it is probably delayed gas operated, and the size of the magazine is about the width of an assault rifle. The only assault rifle type cartridge of the time was the 7.92x33mm kurz (the round used in the MP44), so the weapon probably fires that round, or something similar due to the MP44 and ammunition being made in 1944 as the name of rifle denotes. The grenade launcher is required in order to stall the Castle Tank Boss near the end of the level.
A notable attribute of the K-SMG is that its bullets, being very strong, can sometimes ricochet off walls, similarly to the secondary fire of the Sci-Fi Handgun.
- The weapon is supposed to be an MP40 or a MP44 but with an AK like magazine and a front grip
- If a bot runs out of bullets when firing the K-SMG, the bot will not know it has run out of bullets and keeps trying to fire, becoming absolutely harmless. This is likely due to the fact there is still secondary ammo in the weapon that the bot is incapable of using.