The Zen Armaments “Room Cleaner” Shotgun vz. 1 (commonly known as the RC-1) is a variable-gauge shotgun designed for military, police and general security applications.

The Room Cleaner, designed by former Paragon Initiative designer Elena "Nene" B. Romanova, is a pump-action, variable-gauge shotgun meant to digest several forms of shotgun ammunition. It features several interchangeable parts to customize the gun to the user's needs, including barrels, sights and foregrips.

The most highlighted feature is the Gauge Changer, a system Romanova designed after becoming frustrated with the potency of the typical 12-gauge round. Being Nepleslian, Romanova had seen the power of a 4-gauge shotgun tear a person in two — while they wore body armor. She wanted to be able to switch to that power and, if required, return to smaller shells for better shot placement.

Instead of doing it with barrels, however, Romanova wanted the system on demand.

The Gauge Changer is a system that modifies a chamber and barrel to expand or contract as required.

A reservoir of nanomachines stored in part of the rear of the oversized bolt can, at the flick of switch, stream out of a port in the bolt face to tighten the bore of the barrel and, thus, the chamber. The process takes about 10 seconds. Once completed, the nanomachines have hardened into the nickel-steel alloy of the barrel, which is strong enough to withstand the pressures generated by shotshells.

The nanomachines, when in their reservoir, provide bolt strength when firing 4-gauge shells. The nanomachines receive power from a battery in the pistol grip, which is enough for about 1,000 gauge changes.

The RC-1 is the second entry by Zen Arms to retake the market share of its traditional small arms business. It is marketed as the answer to any shotgun-related question.

As it stood, the market was saturated with surplus weapons from wars past and dead companies. The most ubiquitous was the Westech Trench Shotgun, found for as little as 50 KS in some places. Third-party companies continue to manufacture parts.

The only other active manufacturer of personnel-sized shotguns, Styrling Vervaardiging, had a pump model and an autoloading model. Both were competitively priced.

Zen decided to price the weapon above the Shot 12, but below the Auto 12, and aggressively went after law enforcement agencies and specialized military units.

Pump-action.

A pump-action firearm is typically fed from a tubular magazine underneath the barrel, which also serves as a guide to the movable fore-end. The rounds are fed in one by one through a port in the receiver, where they are pushed forward. A latch at the rear of the magazine holds the rounds in place in the magazine until they are needed. If it is desired to load the gun fully, a round may be loaded through the ejection port directly into the chamber, or cycled from the magazine, which is then topped off with another round. Many shotguns work this way, along with a few rifles.

Safeties: A sliding lever on the left side of the weapon, above the trigger, and a grip switch that must be compressed by the hand gripping the pistol grip to be deactivated. Pump-action release lever: A small button on the left side, just above the end of the trigger guard. Gauge Changer switch: Just to the right of the trigger blade, it is depressed upward to switch gauges. Weapon Sights: Steel rear U-notch sight with light red light catcher; steel front post sight, also with red light catcher. Battery magazine release Pressing the Gauge Changer switch and both safeties at the same time will drop the magazine from the pistol grip. Stock: Rear stock collapses forward to save length.

The RC-1 is built with a mix of milled steel billet and polymers. The use of steel and polymer keeps the cost low while maintaining a hefty weight to absorb recoil. The barrel, however, is made of a nickel-steel alloy, with the outside coated in a metal-based paint.

Field Maintenance Procedure: Routine cleaning and oiling is preferred, but is not recommended until after 4,000 rounds in mild conditions.

Pricing: 700 DA.

• Additional Battery Magazine (40 DA a piece)

• Box of 50 12-gauge Rounds (50 DA)
• Box of 100 Rounds (100 DA)
• Box of 300 Rounds (200 DA, Buy one get one half off.)

• Black Nylon Sling (10 DA)
• Reflex Sight (100 DA)
• Wooden Foregrip (80 DA)

This was submitted by Doshii Jun in this thread and it was approved by Wes in this post on 11/04/2011.