EPP weapons are typically constructed around one of two basic designs - parallel conductor "rails" that accelerate the projectile along them, or a series of sequential conductor units positioned down the length of the weapon's barrel.
The kinetic force created by the rail design is much more powerful than the latter, but its power requirements are proportionally greater. This design also requires more precise engineering and higher quality materials to compensate for the propellant force's impulse to "splay" the weapon's rail conductors, and the highly charged rails make it more dangerous to unprotected user.
The most common form of firearm among the human populations of the Orion Spur, electromagnetically-propelled projectile (EPP) weapons impart kinetic energy to a projectile using electromagnetic force. Such weapons are employed at almost every scale of warfare - from concealable, personal sidearms to planetary defense batteries.
Weapons Employed by the HDC
Most infantry firearms employed by HDC troops are based on EPP technology, and all such weapons designed for "armored operators" (troops equipped with ACE combat suits) are based on the aforementioned "rail" design. The superlative materials and engineering available to the HDC, in addition to the protection offered by ACE technology allows for mass production of these more powerful designs, where other organizations might have be forced to settle for less effective models.
Weapons designed for armored operators are tremendously heavy and produce immense recoil, such that they are generally useless to an unassisted operator. These weapons connect with the onboard network of the user's ACE and receive additional power supplies from its reactor via interfaces on the wearer’s palm. This allows the user complete and instantaneous control over all of their weapon’s functions through their neuroconnector. If separated from the user’s ACE for an extended period of time, the weapon will lock unless activated by the original user or presented with an unlock code by an affiliated trooper. They can be instructed to irreparably seize or detonate their onboard ammunition after repeated attempts to interface with the weapon without inputting the proper credentials.
Storage of weapons and other supplies is accomplished by magnetic locks on the surface of a trooper's armor that disengage when grasped. This eliminates the need for bulky storage equipment.
HDC UPA (Universal Protean Ammunition)
Most HDC small arms fire programmable, multi-purpose ammunition known as "Universal Protean Ammunition" that is interchangeable between most other infantry weapons. UPA are bullets loaded with a micro-explosive core that can be programmed to detonate under certain circumstances, such as distance or via proximity fuse. The benefits of this variability are myriad; it allows, for example, the bullet to be detonated behind barricades to injure defiladed targets, explode just before impact to shower the target with shrapnel, after impact to shred lightly armored targets or stay intact to penetrate heavy armor. This flexibility is compounded by the ability to alter the propellant charge of the weapon, allowing the user to control the speed at which the projectiles reach their target.
HDC Infantry Weapons
DCE22 Assault Rifle Employed as the primary weapon system of M-TAC rifle squads, the DCE22 is a flexible workhorse capable of fulfilling a myriad of combat roles. Loading UPA rounds and capable of mounting a wide variety of additional attachments such as enhanced targeting systems, retractable bayonets blade and rocket launchers, this weapon is one of the most common distributed to HDC infantry.
DCE112 Heavy Machine Gun M-TAC support gunners are among the few specialists trained in the use of the DCE112 weapon system. The heavy machine gun's hyper-rapid rate of fire and tremendous ammunition consumption make it unsuitable for widespread use, but it is the superlative suppressive weapon. While the DCE112 is designed to use UPA rounds from a backpack-mounted ammunition hopper, to supplement its tactical applications it is commonly deployed with specialized ammunition that is loaded directly into its feed.
DCE24 Designated Marksman Rifle Assigned to M-TAC fireteam marksmen, the DCE24 is a variant of the DCE22 Assault Rifle designed for longer ranged engagements. Mounting advanced targeting and scanner systems, the DCE24 mounts a longer barrel and more powerful conductor rails that sacrifice the flexibility and rapid cycle time of its smaller cousin for greatly enhanced accuracy and firepower.
DCE-G8 Combat Shotgun One of the few HDC weapons not designed to mount UPA rounds, the DCE-G8 is typically only assigned to specialists that operate in close-combat battlefield roles, such as breachers and pointmen. While still an effective rapid-fire weapon, the DCE-G8's heavy ammunition tends to lose accuracy at range but is capable of loading a wide array of specialized payloads, including high explosive, antimaterial and shrapnel. Unlike UPA-capable weapons, the drawback of the DCE-G8's design is that each specialized ammunition type must be carried and loaded manually by the operator.
DCE14 Submachine Gun A favored weapon of close-range shock troops such as MANTIS teams, the DCE14 features a much shorter barrel than similar HDC weapon systems. This enables a significantly shorter cycle time and allows for a hyper-rapid rate of fire, albeit at the loss of some measure of accuracy and firepower.
Non-EPP HDC weapons
HDC tactical analysts are cautious of a over-reliance on EPP weapon systems in HDC combat loadouts. While heavily shielded, these weapons are susceptible to many issues that traditional firearms are not - such as electromagnetic interference, software failure or digital sabotage. For this reason, all HDC combat troops are equipped with deflagrant sidearms in the case of a primary weapon failure.
FA277 CPM Sidearm Referred to jokingly as a "dumb" weapon by its operators, the FA277 is the sidearm assigned to M-TAC armored personnel. A traditional, "chemically-powered munition" weapon with no electronic components, the FA277 is meant as a last-ditch resort in the circumstance, however unlikely, that the operator experiences a primary weapon system failure. Still, the sidearm's heavy ammunition and robust design make it known for its power, accuracy and unparalleled reliability.