Scaled down from it's predecessor, the Hf|Kanone 41', which validated it's own existence as an anti-armor device, designed for melting treads into slag and boiling the crew alive. Well, armor did get thicker as the war progressed and the various elements in Höllenfeuer munitions became more refined and hotter-burning, an effective method of infantry support weapon was brought up for review by the DiG Lab 14C(Infantry armaments research lab in Essen). The concept of the HfK 51' was to provide obscenely destructive firepower to well-trained infantrymen (pyromaniacs may apply for training). After the initial testing phase, the effects of such a munition/delivery system are practically explosive when the stream/onslaught of hyper-ignited fuels forced down a barrel and and launched through an "Incendiary Acceleration Muzzle Device" (Feursturm Gerat 52') that condenses and forces the stream/blast of insane thermobaric force into a an almost semi-conical form making the blast act like a mix between an armor-melting wedge and that of a small-caliber grenade mixed with the utter-horror that is grapeshot on a crowded ships-deck if used on infantry. This concept, design and application of both caught the eye of Reichskanzelor Speer within a week. Soon enough (with Speer's direct financial and scientific support), the first models of the HfK 52' were rolling off the assembly lines and troops were being trained in it's use daily. Soon-enough, the HfK 52' was gaining immense popularity from Panzerjäger infantry units due to the practical application of something that reaches a thermal-threshold high enough to make phosphorous hit it's plasma-flashpoint.....well, the flexibility in regard to ambush tactics are utterly immense. Not counting the horrifying end-results of it's use as an anti-infantry tool during the Transition-War were of enough destructive effect to be written down in the history books right next to Mustard Gas and Agent Orange in regard to the nightmarishly murderous effects on human beings.
Name: DiG(Krupp) - Modell 1952 Höllenfeuer Karabiner.
Cartridge: 25mm Höllenfeuer (Phosphorous, Tar(powdered form), solid-state "Komet" type jet fuel, Nitro-Benzine, petro-industrial waste byproducts, Hydrazine and "Warp Fire Resin") burns at 1650 Kelvin)
Munition info: fav.me/d6mbqyf
Ammunition Capacity: Ten round box mag (based off of the Flak 38's magazine), Rotary drums are available for pintle-mounted and larger-range variants.
Action: Primer-Actuated Flapper-Locking
Rate of Fire: Semi-Automatic (FAO)
Muzzle Velocity: 2,877 f/s (has been known to function like grapeshot from a field-piece at certain ranges)
Sights: DiG Modell 51'
#1: The "ridges" on the right are an air-intake forcing cooling.
#2: Spent casings tend to be near "orange" when ejecting due to the intense thermal radiation caused by the munition when firing.
#3: The HfK 52' feeds from the left in a manner almost akin' to the FG42.
#4: The three gauges on the right side show just how hot certain portions of the mechanism are getting; IE, "Gauge 1 = Chamber/bolt", "Gauge 2 = Barrel", "Gauge 3 = receiver".
#5: There is a switch on the left-side (near the safety/fire-selector) that can be toggled to forcefully vent the buildup of heat should the mechanism start getting "a bit too damn hot" (Upon doing so the air-intake forces the hot-air outside via forced thermal induction, this usually causes the water-molecules in the air near said vent to become steam).