M7 Caseless Submachine Gun

The M7/Caseless Sub-Machine Gun is a widely used United Nations Space Command firearm.

There is also a version, the M7/Caseless Suppressed Sub Machine Gun, which is equipped with a external suppressor.

Introduction
The M7/Caseless Sub-Machine Gun is a dual wieldable weapon seen in Halo 2, as well as the Halo 3 Beta, and is going to be in Halo 3. It is not a very powerful weapon and has slight design as well as technical changes in Halo 3.

Summary
The M7/Caseless Sub-Machine Gun is a fully automatic, gas-operated, magazine fed, dual wieldable, short range weapon. The SMG fires 5x23mm Caseless FMJ (Full Metal Jacket) rounds from a 60 round mag with an extremely high rate of fire (which actually leads to tremendous recoil and forces the barrel upward after continuous fire). It also sports a retractable stock and foregrip. The SMG lacks range and power as well as accuracy so it is strictly a short range weapon. The Halo 3 SMG is relatively the same with minor design and technical changes.

Physical Description And Appearance
The M7/Caseless Sub-Machine Gun is an automatic UNSC sub-machine gun that fires 5x23mm Caseless FMJ (Full Metal Jacket) rounds. It fires from a 60 round magazine which is actually placed horizontally on the left side of the weapon due to the way it fires.

The SMG has a polymer handle, foregrip, and stock, as well as a titanium body, and is gas-operated with a rotating breech. The SMG must be cocked before it can fire the first round. The bolt to cock the weapon is located on the right side of the gun and does not move during operation. From then on, the gases from previous rounds force the breech to rotate and chamber a new round. Once the mag is empty, the bolt (although not illustrated in Halo 2 or Halo 3) can either be pulled back and locked or it can be fully cycled after a fresh magazine has been housed. If it is first pulled back and locked, then it must be pushed forward in order to chamber a new round. There is no ejection port due to the nature of the rounds fired.

The SMG, having a rifled barrel, is 47.5cm long with the stock retracted and has a maximum length 62.8cm when the stock is fully extended. The stock is fully adjustable. The Halo 3 SMG is basically the same but has a slightly shorter foregrip and has red dots at the receiver end of the mag. This weapon does not possess a safety and is dual-wieldable.

This weapon first appeared in Halo 2 and is returning in Halo 3.

Advantages
The SMG is an excellent suppressive weapon. When firing upon a Battle Rifle user or a Sniper user, the scope will be turned off once the target hits, reducing their accuracy and giving you the advantage.

The SMG is also good at close range, the preferred range for this weapon. If you are close enough, all of the bullets will hit the target and will be able to disable the shields faster than at medium range. It is supremely deadly against unshielded foes.

Changes in Halo 3

 * Red dots at the receiver end of the mag
 * Slightly shorter foregrip
 * Increased accuracy
 * Increased range
 * Increased rate of fire
 * There is now a short delay before the barrel actually starts to climb
 * Slightly less damage

Against the Covenant
Employed against the Covenant, the SMG is a very powerful close-to-mid range weapon. When fired in short bursts, it can easily decimate whole squads of Grunts. The SMG is also very useful against Jackals, with the 5mm curiously "stunning" the Jackal. The SMGs large magazine size is also useful for taking out the aerial groups of Drones. Employed against Elites, Dual SMGs are extremely deadly, made even more so by firing them "out of phase". However, SMGs are not effective against Hunters, or Brutes.

Against the Flood
Like the M6D Pistol of Halo: Combat Evolved, SMGs' are effective for eliminating Flood Carriers. When Dual Wielded, SMGs are extremely deadly, capable of taking out large groups of Infection Forms and Combat Forms alike.

Ammunition
The SMG uses a radically different kind of ammunition than the kind found in other UNSC weapons called the M443 Caseless Full Metal Jacket round. This ammunition is classified as "caseless," meaning it does not have a metallic casing surround the powder and sealing the bullet, propellant, and primer together. Instead of using this casing, the round uses a combustible adhesive to seal these components together. Because the chemical "casing" is vaporized when fired, there is no need to eject spent brass casings.

This feature is very beneficial. It reduces friction inside the magazine, one of the main causes of jamming in weapons. It also negates the need to expel casings, as mentioned above. This is important, as a user wielding two M7s at once would not want to have hot brass flying in his face from the eject port of the weapon in his left hand. The projectile itself is "jacketed," or coated, in metal (possibly copper or steel) 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.

Although 5x23mm (20 caliber) rounds would normally be considered small by modern SMG standards, the caseless layout might have an effect on the amount of gas produced when the propellant is ignited, causing a higher velocity, while the full metal jacket would ensure higher penetration than a normal lead point. This, combined with the weapons very high rate of fire, would make it powerful at close range from a realistic standpoint. The muzzle climb of the weapon would also indicate higher pressure inside the weapon, higher than what would normally be expected for such a modestly sized cartridge.

Influence
The M7 appears to take its design from three real-world firearms. The first is the Heckler and Koch G11, a caseless prototype assault rifle developed in the 1980's. The second is the Fabrique Nationale de Herstal P90. The last one being the H&K MP7. The M7 takes its concept from the G11, and its design from the latter two. As the MP7 and P90 are both personal defense weapons, it can be assumed that the M7 falls under this classification as well. Its slanted front, foregrip, and expandable stock come from the MP7; while its ergonomic grip and the horizontal magazine in a bullpup configuration come from the P90.

Character Compatibility

 * Elites
 * Spartans
 * Marines
 * Brutes (have animation but not used)
 * Jackals
 * Drones (have animation but not used)
 * Flood Combat Form (Human)
 * Flood Combat Form (Elite)

Related Links

 * M7 Caseless Suppressed Sub Machine Gun

Trivia

 * It seems to be SPARTAN-117's weapon of choice in Halo 2, when dual-wielded, and he is frequently seen dual-wielding SMGs.