R405

The R405 is a 7x47mm select-fire, pulse-action assault rifle in limited usage by the Sol Defence Corps as part of the Final Frontier Project. Built by German manufacturer OBD, the rifle incorporates the latest technologies available to the firearms industry into a singular, effective package. While costing nearly twice as much as the previous standard-issue rifle, the M7A3, the weapon compensates by coming loaded with a smart fire control system and built-in screen displaying the ammunition count and various other statistics of the rifle.

The rifle is designed for combat in zero-gravity, using a magnetic sling attachment, oversized trigger guard and built-in recoil management systems to help keep the weapon zeroed and pointed at a target even as recoil might attempt to propel the user backward in microgravity. With an oversized trigger and adjustable, dynamically-shaped buttstock, the weapon is designed to be fielded with a hardsuit. It feeds from a 33-round magazine and uses a lightweight alloy and polymer design to allow the gun to come just under 3 kilograms even when fully loaded.

Background
Following the conclusion of the Martian Revolution, the SDC was faced with the prospect of utilising a new firearm for fielding by the Final Frontier Project. While their existing M7A3 rifles were still reliable and combat-worthy as ever, they lacked the features and technology mandated by the SDC to supplant troops on worlds where the nearest supplier or gunsmith would be billions of miles away.

As a result, a new contract was set out to make a service weapon capable of functioning under any condition, be able to diagnose itself and possess enough stopping power and versatility to be fielded and used in any situation. A contract was placed in 2106, with trials narrowing down to OBD, a relatively new German firearms company, and Royal Arms Manufacturing, the manufacturer who had designed the M7A3 prior.

OBD began designing the rifle, with efforts spearheaded by chief designer Karl Ottomar, eventually delivering the first prototypes in July 2107 to the SDC's testing offices as the R400.

Then-Rear Admiral Matthew Gonzalez had been eyeing the rifle ever since its introduction onto the stage, and with the approval of SDC Admiralty had requested that OBD produce 10 initial R400 rifles for closed testing.

Unfortunately, the rifle had come into problems with its own, with design defects leading to a subpar manufacturer that OBD had contracted out. Stoppages were frequent, and the then-activated automatic jam-clearance feature had only served to make feed issues worse, with cartridges even being damaged by improper feeding. The screen also had reliability issues; cracking the glass would lead to the screen underneath becoming completely illegible. The rifle was sent back to the drawing board, humiliatingly, and OBD had to redesign several features of the rifle, as well as hire a new manufacturer.

Adoption
Five iterations later, the R405 was unveiled once more to the SDC. The automatic jam clearance was removed, ammunition issues were fixed, the bolt carrier group was redesigned and the glass screen panel was replaced with aluminium oxynitride. Additional cost-cutting measures were implemented to bring the previously-obscene price tag of over 4000 SOL to a slightly more reasonable level. The rifle was put into testing once again, where it had performed perfectly and was praised among troops for its features.

The R405 was promptly introduced into official SDC service, with 85,000 units currently in circulation. The SDC has contracted OBD to produce 70,000 more units for personnel.

Design
The R405 is one of the most technologically advanced firearms in military service. It utilises a pulse-action, firing from a closed linear bolt. With a conventional layout, the weapon is designed to be easy to reload and field despite being longer than a bullpup.

The R405 features ambidextrous controls and a double-sided ejection port and non-reciprocating charging handles. The ejection port can be changed by flipping a switch located next to the weapon's main screen.

Screen
The weapon has a built-in screen underneath the rear sight, displaying information such as ammunition count and fire mode. In addition it can be switched to display weapon diagnostics, including its temperature, accuracy rating, and quality rating, with the weapon able to detect and suggest when to have it cleaned or repaired.

The weapon features an integrated IFF interrogator and rangefinder, cooperating with whichever optic is mounted to provide data for whatever is aimed downrange. Ballistics and trajectory for rounds are calculated by the weapon's built-in computer.

Adjustability
Due to the electronic action mechanism, most features of the weapon can be dynamically adjusted on the field without tools or disassembly. This includes:


 * The trigger pull, able to have its pull weight adjusted (ranging from 2 kg to 5 kg), as well as being able to switch between single- and double-stage trigger pulls.
 * The fire rate, able to be adjusted from 800-1500 rounds/minute, tuneable from the weapon screen.
 * The cyclic rate, able to be adjusted independently (or together with) the firerate to control recoil.