M6D magnum

The M6D Personal Defense Weapon System (abbreviated M6D PDWS), otherwise known as the M6D Magnum Sidearm and commonly referred to as the M6D Pistol, is a United Nations Space Command sidearm and is one of the variants of Misriah Armory's M6 Sidearm series.

Introduction
The M6D Pistol is a common UNSC sidearm and was probably first put into service around 2524 (based on Fall of Reach). It is a model of the M6 series pistols that were distributed to members of the UNSC Navy and the Spartan-II Program. This particular M6 weapon is featured in Halo: Combat Evolved and in Halo 2 (although it was not usable in Halo 2) and is considered a powerful weapon when compared to other M6 series weapons. Its flesh damage as well as accuracy and range are higher than other M6 models. Its rate of fire is also rather higher. This model cannot be dual-wielded in-game, although this is because the MJOLNIR Mark V can only track one weapon at a time.

Summary
The M6D is a semi-automatic, recoil-operated, magazine-fed, magnum caliber handgun. It is most likely striker-fired, due to the fact that there is no external hammer. It fires the M225 SAP-HE (Semi-Armor Piercing, High Explosive) rounds from a 12 round magazine. It has a decent high rate of fire (3.5 rounds/sec or 210 rounds/min) with a very long effective range, being able to hit a target accurately up to about 90-95 meters. Its real range, however, is 122.5 meters (real range being how far the bullet can actually travel). The weapon’s accuracy alone is quite precise and has a very small shot spread at close and medium ranges. This, combined with its decent damage against current shield systems, makes it an acceptable weapon of choice when faced with shielded opponents. It is, however, even more effective against flesh and hard/soft armor, being able to kill most targets in 1 shot to the head or a couple of shots to the body (depending on the target).

Technical Specifications
The M6D Pistol is a DA only (possibly) UNSC handgun capable of using heavy pistol rounds (magnum loads). This weapon has a polymer handle, making it comfortable in the user's hands, along with a titanium alloy body, and utilizes the M225 12.7mmx40mm SAP-HE round (.50 caliber) which leads some to believe it's a PDWS. It fires these powerful rounds from a 12 round, single stack magazine that does not fit flush into the magazine housing. A flush magazine fits completely inside the housing and does not protrude out of it.

The M6D is semi-automatic and fires using the short recoil principle. This means that the trigger needs to be pulled after every shot for the next round to be fired. Because it is semi-automatic, the gun will cock itself after every shot due to recoil and will continue to do so until the magazine is empty. The recoil comes from the gases of the rounds fired. The gases force the slide, located on the top of the gun, backward. The slide not only absorbs the force of the gases but it also uses the force to eject spent casings out of the ejection port and load new rounds into the chamber. It also re-cocks the gun. Of course, before the first round can be fired, the round must be chambered. This is done by first, inserting a magazine with ammunition into the grip of the weapon (where most semi-auto pistol mags are inserted today) and second by pulling the slide back completely and letting it launch forward, chambering a round on the way. There is a small, red rectangular box on the flat back of the slide that protrudes out slightly when the weapon is cocked. Once this is done, the safety (which is not visible on the in-game model) must be switched up or off or the weapon will not fire. Once all the rounds have been spent, the slide catch, a rectangular lever located above the trigger on the body, is forced upward and “catches” the slide by a little notch. To reload, the empty magazine must be removed and this is done by using the magazine release button which is located on the grip. Once the empty mag is out, a fresh one can be inserted. Once the fresh mag is inserted, the slide catch is pressed downward and the slide chambers a round. If there is still a round in the chamber when reloading, than a simple ejection of one mag and an insertion of another, disregarding the slide catch portion of a normal reload, is all that needs to be done. The M6D is a very basic pistol when it comes to technology. It is a rather large handgun, having an overall length of 26.7cm and possesses a barrel with traditional rifling, improving accuracy by spinning the bullet. It has a chrome silver color and operates like most modern day pistols. It also has rear sights (does not possess front sights due to the scope). The control lever serves as a safety (and most likely a decocking lever). If it is also a decocking lever this would most likely be done by pushing down on the lever past the safety point. This weapon features a KFA-2 2x optical, smart-linked scope. This scope links directly to a Spartan’s HUD or a marine eye piece. It also has a large trigger guard, which helps prevent the user from dropping it and a chrome barrel which helps prevent corrosion. It does not possess company writing like modern day pistols do.

Changes From The M6C

 * Color changed black to silver chrome.
 * Increased accuracy, range, damage, magazine capacity.
 * Added KFA-2 2x scope.
 * Lowered rate of fire.
 * High explosive ammunition.
 * Non Dual-wieldable. (Due to the fact that the MJOLNIR Mark V armor can't track two weapons simultaneously)
 * Significantly stronger rounds.

Tactical Uses
The M6D Pistol is a close-long range weapon and is suitable as a primary weapon. With its high effective range and accuracy as well as high damage, it is useful for engaging almost any target at any range, fully being an all-purpose sidearm.

The M6D is useful against any target that is encountered throughout combat. Enemies such as Grunts and Jackals can be quickly dispatched with one well placed headshot and enemies like the Flood can be dispatched in as little as 1-3 shots to the chest, it's generally best use against sniping Flood Carrier Forms where they're in firing range. Unshielded Elites also go down in one shot to the head. However, when Elites have shielding more shots are required to kill them (6 shots to the head of a Minor, 8 shots to the head of a Major, 10 shots to the head of a Spec Ops, and between 18 and 24 shots to the head of an Zealot. Hunters also only require one shot to their exposed flesh to kill them.

Shots needed to take down your opponents vary based difficulty setting. The info above is taken from the Normal difficulty setting.

In Multiplayer, some users may use the M6D as their all around weapon due to its high accuracy. But in general, the M6D is very unreliable as it's weak against shields, give time for your opponents to strip you down before you can do damage. However, this has not stopped some players, who like it so much that a new term has arisen for using it as a distance weapon: "Pistol-sniping."

Ammunition
The M6D uses 12.7x40mm M225 SAPHE (Semi Armor Piercing High Explosive) .50 Caliber Ammunition Magnum loads. . These rounds have a metal coating of copper or cupro-nickel around the perimeter of the projectile while the projectile itself is hardened and hollowed out and filled with additional primer. The projectile will deform and explode shortly after penetration. When the round hits a hard object such as body armor, the metal coating will deform, allowing for the hardened projectile to continue through into the target because most of the energy is kept with the hardened projectile. The round quickly deforms after penetration. The reason for making these rounds semi-armor piercing instead of flat out armor piercing is to prevent the projectile from leaving the target and wounding someone that may be behind it. This is why the projectile deforms after penetration. These rounds are high explosive meaning that the round is designed to explode after it has come in contact and penetrated a target.

These rounds are somewhat effective against shielding systems. This is because the rounds are designed to explode. When the projectile hits the energy shield system, the primer ignites and explodes causing a good deal of damage to shield. The bullet’s explosive properties allow it to perform well against vehicles also.

Influences
Another possible influence on the design of this weapon was the FP-45 Liberator, a weapon designed in the United States during World War II. The long handle, but short barrel as well as the covered hand-grip are obvious features.

Also, the pistol weapon in Marathon, Bungie's previous FPS, had a visible scope. It is possible this is where Bungie's idea of giving a pistol a scope originated.

Trivia

 * The M6D pistol is the first weapon you use in Halo CE.
 * Captain Keyes gives Master Chief (John-117) a M6D pistol.
 * M6D pistols are the only pistols that have scopes.
 * It has been said before "It's either the world's biggest pistol or the smallest rifle."
 * The ammo packs for the M6D have a declaration lettering code: M225 12.7x40mm SAP-HE
 * According to Jason Jones there was a Covenant sabotage mission to dispose of all M6D pistols because they were too powerful which is why they weren't in Halo 2.
 * Bungie was not happy on how the M6D Pistol and the MA5B behaved in Halo: Combat Evolved. They complained that the M6D behaved more like a rifle and the MA5B behaved like an SMG. Thus, in Halo 2, the M6C, BR55, and the SMG were born. Robt McLees, a weapons designer in Bungie, commented, "Now we have a rifle that behaves like a rifle, an SMG that acts like an SMG, and a pistol that acts like a pistol.
 * The M6D has Japanese Kanji (The Chinese character "Seven") written on it.
 * In Halo: CE when a person with the M6D looks down, the gun will be pointed downward but the character will be facing forward, making it look like the character is acting like a normal person. This is often used in many machinima, notably Red vs. Blue.
 * It can take up to a magazine and a half to destroy a Banshee in campaign (fully destroy, not just kill the pilot).
 * Bungie stated that the M6D pistol was originally less powerful but was changed to fix a bug, but wasn't changed back to its original status.
 * Many players did not like how it could act like a Sniper Rifle during multiplayer. As it was a easy weapon to find, and it could kill you in three headshots. In no-shields mode, it only requires an incredible one headshot, or three chest shots.
 * It is arguably the best weapon to use against Combat Forms in Halo: CE. A single shot to the head can bring a Form down almost every time, even on Legendary. This is especially useful on levels such as The Library.
 * Technically, if you hold down the fire trigger in the Xbox version, it will fire automatically, but it will not be much faster than regular fire.
 * With the exception of Truth and Reconciliation, it appears in every level of Halo: Combat Evolved.