|Manufactured:||2004(Introduced in Halo 2)|
|Type:||197 caliber rounds|
The M7/Caseless Submachine Gun, more simply known as The SMG, is a United Nations Space Command infantry and special operations weapon. A suppressed version of the M7/Caseless Submachine Gun, known simply as the M7S Submachine Gun, is also available for UNSC special operations.
The M7/Caseless Submachine Gun is a fully automatic UNSC submachine gun that fires from a 60-round magazine which is placed horizontally on the left side of the weapon. Due to the odd horizontal placement of the magazine on the weapon, it can be assumed that the magazine utilizes a circular ramp where the magazine meets the breech. This rotates the vertically stacked rounds in the magazine 90 degrees until they align with the horizontal breech. An example of this can be seen in the present day Fabrique Nationale P90 SMG.
The SMG has a polymer handle, folding fore-grip, collapsible buttstock, iron sights, and a titanium body. Prior to firing when empty, the SMG must first be cocked to chamber the first round. The charging handle is located on the right side of the gun and does not move when firing. Once the first round is fired, the gases from previous rounds force the breech to rotate and chamber a new round. Once the magazine is empty, the handle, although not illustrated in-game, can be either pulled back and locked or it can be fully cycled after a fresh magazine has been inserted. If it is first pulled back and locked, then it must be pushed forward in order to chamber a new round. The magazine release button is located between the red dots on the left side of the receiver and needs to be pressed before the magazine can be released. There is no ejection port due to the nature of the rounds fired.
The SMG has a rifled barrel that is 15 centimetres (5.9 in) long. The weapon is 47.4 centimetres (1 ft 6.7 in) long with the stock retracted. The stock is always retracted in games, and has a maximum length of 62.7 centimetres (2 ft 0.7 in) when the stock is fully extended.
The SMG can also be affixed with a suppressor, flashlight, reflex sight, and smart-link scope. In this configuration, the weapon is designated as the M7S Submachine Gun.
The SMG uses 5x23mm caseless ammunition, a radically different kind of ammunition than the kind found in other UNSC weapons. This ammunition is classified as "caseless," meaning it does not have a metallic casing that holds together the bullet, propellant, and primer. Instead of using this casing, the round uses a combustible adhesive to seal these components together. Because the adhesive and propellant are both vaporized when fired, there is no need to eject spent casings. Though not featured in-game, contemporary caseless ammunition is highly susceptible to cook-off, the accidental firing of rounds due to built-up heat in the receiver.
This feature is very beneficial. In addition to increasing fire rate by removing the extraction and ejection phases of the weapon's cycle, it reduces friction inside the magazine, one of the main causes of jamming in weapons. This is also conducive to dual-wielding, since the user need not concern themselves with hot brass expelled from the weapon held in the left hand. The projectile itself is jacketed in metal (usually a copper alloy in standard military ammunition) to aid in penetration of the target. Caseless rounds are actually embedded into the block of propellant, reducing their length, allowing more ammunition to be stored in a smaller space.
The SMG's 5x23mm (.197 caliber) rounds, while smaller than most other SMGs, could classify it as a PDW (Personal Defense Weapon), from which it has already taken several design forms.
Since it has a larger magazine than the MA5C Assault rifle, players will have to reload less often than if they were to use the MA5C. Because of the large magazine, one can easily continue firing through targets with little pause for reload. Like most UNSC firearms, the SMG is extremely deadly against unshielded targets, and can kill them rather quickly. In addition, the SMG serves as a better close range secondary weapon when already armed with a Battle Rifle. In combination with the Battle Rifle, the SMG makes a reliable close range support weapon when shotguns and swords are not available. The SMG serves better than the MA5C at close range due to its larger magazine and faster firing-rate, and is an excellent choice of replacement for the Assault rifle in close combat situations, but not however at medium range.
The SMG can also form part of the most effective dual-wield combos in the game. The SMG, when dual-wielded with a Plasma Rifle, can be a deadly combination because the Plasma Rifle depletes the opponents shields and the SMG's armor piercing rounds do the rest. Another favored combo is dual-wielding the SMG with the Plasma Pistol, often referred to as the "Noob Combo." The charged shot from the Plasma Pistol will deplete the shield of your opponent and a full burst of SMG fire to tear through the now-exposed armor. In Halo 3, the SMG has been improved. By itself, the SMG can be an extremely devastating weapon in close-quarters combat, simply because of its high ammo capacity, lightning-fast melee, and fast rate of fire.
The SMG has received the nickname "bullethose" due to its high rate of fire, low accuracy, and inability to be fully controlled when fired in full-auto. The SMG's primary limiting factor is its poor accuracy, which limits its use to close range. At close ranges the SMG is very powerful and is only outperformed by the Shotgun, Energy Sword, and Gravity Hammer. Like most other Human weapons, the SMG performs relatively poorly against shields, though this weakness can be negated by wielding it in conjunction with a plasma rifle or plasma pistol. As stated before, the gun has recoil which causes the barrel to climb after continuous fire and will climb faster if players dual-wield it. This forces the players to continually move their reticule down to keep the enemy in their sights but is not a big limiting factor. This, as well as the poor accuracy can be slightly countered, using a burst-fire technique, unleashing about five bullets each pull of the trigger. It also has the problem of an extremely long reload time when dual-wielded, making it easy to be killed while changing magazines. This problem however can be solved by volley firing the weapons, so while one is reloading the other is still firing. This tactic reduces the power of having two SMGs but gives the advantage of approximately 40+ seconds of non-stop firing.