MechaBay

Big Gun

Long-range sniper gun emplacement developed by the Principality of Zeon.
Jenxi Seow Published 23 Jun 2025 Updated 23 Jun 2025
Big Gun

The Big Gun was a long-range sniper gun emplacement developed by the Principality of Zeon for use by mobile suits piloted by snipers from the Living Dead Division during the One Year War.

This powerful long-range beam cannon was specifically designed to provide devastating firepower against Earth Federation Forces units operating in the Thunderbolt Sector.

History

The Big Gun was developed by the Principality of Zeon as a specialised weapon for long-range engagements in the debris-filled Thunderbolt Sector. The weapon was assigned to the Living Dead Division, a unit composed of veteran Zeon soldiers who had suffered severe injuries and required prosthetic limbs or life support systems.

During the One Year War, Big Gun emplacements were strategically positioned among the debris of the destroyed Side 4 colony to provide overwatch and long-range fire support. The weapons were used to pick off Earth Federation Forces units, particularly those of the Moore Brotherhood, who were attempting to secure the sector.

The Big Gun proved highly effective in its intended role, with its devastating beam cannon capable of sinking a battleship with a single shot. The weapon’s positioning among the colony debris provided excellent concealment whilst offering clear lines of sight across the battlefield.

After the war, at least one Big Gun continued to see service on Earth when Daryl Lorenz used it whilst piloting the prototype MS-06R Psycho Zaku Mk-II against the Pegasus-class assault carrier Spartan.

Design

The Big Gun was an advanced beam weapon system that represented a significant departure from conventional mobile suit armaments. Rather than drawing power from the mobile suit’s reactor, the weapon was entirely self-contained with its own power generation system.

Power system

The Big Gun was powered by three onboard large generators, which provided the enormous energy requirements necessary for its devastating beam output. This independent power system meant that the weapon did not drain the mobile suit’s own reactor, allowing the controlling unit to maintain full operational capability whilst operating the weapon.

The use of dedicated generators also enabled the Big Gun to achieve power levels far exceeding those possible with conventional mobile suit-mounted beam weapons, resulting in its extraordinary destructive capability.

Weapon specifications

The Big Gun’s beam cannon was capable of delivering enough energy to sink a battleship in a single shot, making it one of the most powerful directed-energy weapons deployed during the One Year War. The weapon’s immense power came at the cost of barrel longevity, as the intense energy output caused the barrel to wear out with use and required replacement after firing a certain number of beam shots.

Operational deployment

The Big Gun was designed as a stationary emplacement that required mobile suit operation. The weapon was typically deployed in concealed positions that provided excellent lines of sight whilst offering protection from return fire. In the Thunderbolt Sector, the weapons were hidden among the debris of destroyed colonies, making them difficult to detect until they opened fire.

The weapon’s design incorporated a tripod mounting system that provided stability and allowed for precise targeting. The tripod featured an extension mechanism that enabled height adjustment to optimise firing positions and angles.

Tactical employment

The Big Gun was employed as a long-range precision weapon, designed to eliminate high-value targets with single, devastating shots. The weapon’s tactical role included:

  • Elimination of enemy capital ships
  • Long-range support for mobile suit operations
  • Area denial through threat of engagement
  • Precision strikes against fortified positions

The weapon’s ability to remain concealed until firing made it particularly effective in ambush scenarios, where Federation forces would be engaged without warning from extreme range.

Known operators

Behind the scenes

The Big Gun was designed by Yasuo Ohtagaki for the Mobile Suit Gundam Thunderbolt manga series. The weapon was later adapted for the animated OVA series with designs by Katoki Hajime and Seiichi Nakatani.

The weapon reflects the harsh realities of warfare in the Thunderbolt Sector, where debris fields and environmental hazards necessitated the development of specialised weapons and tactics.

Appearances

See also

  • Living Dead Division
  • Thunderbolt Sector
  • MS-06 Zaku II