A Pulse Submunitions Rifle is a formidable Tau Battlesuit weapon system of the Tau, and is an advanced Pulse Weapon that utilises pulsed induction fields to propel lethal micro-bursts of plasma over extremely long ranges. A Pulse Submunitions Rifle is a newly developed form of Pulse Weapon, designed to saturate large areas with plasma pulses at range. Whilst it possesses a slightly shorter range compared to a Pulse Rifle, the scattering nature of its firing allows it to bypass cover more effectively to target entrenched enemies within. Pulse Submunitions Rifles were first developed as primary Battlesuit weapon systems for XV9 Hazard Battlesuits, to complement their role as close range fire support, and thus far have not made their way onto any other deployment platforms.
Shas’O Vesu’r Ra’lai is a notable Tau Commander who pilots an XV9 Hazard Battlesuit, and wields an experimental version of a Pulse Submunitions Rifle as his primary armament. The weapon he wields sacrifices a degree of strength and width of blast radius in favour of a higher rate of fire, and the ability to be loaded with several potent, yet limited issue, warheads. Whilst powerful, they are currently extremely experimental as their barely contained power can damage the Battlesuit itself.
A Pulse Submunitions Rifle works by electromagnetically accelerating plasma shells down its barrel. In effect, it is a miniature mass accelerator. On firing, a ferromagnetic, solid slug is chambered from the magazine and turned into plasma by electromagnetic induction, as it would be relatively easy to alternate the coil current at frequencies sufficient enough to heat the coil to an extreme temperature while keeping it in the chamber. The solenoid is then charged fully, propelling the newly produced plasma out of the gun at an extreme velocity while keeping it cohesive. Though this electromagnetic field continues to keep the plasma together until impact, residual plasma is expelled from the barrel to produce the weapon's considerable muzzle flash. Maintenance of the field is also aided by a bolt-like apparatus, which increases the field strength and therefore the range. Without the electromagnetic field, the plasma would all dissipate at the barrel mouth, producing a weapon with a range of approximately twenty centimetres.
The power required to generate these immense electromagnetic fields comes from the secondary magazine which is effectively a very powerful and dense rechargeable battery in the weapon's stock. It is changed less frequently than the primary power pack, and can be recharged from the firer's suit or combat armour. Vehicle-mounted Pulse Weapons are usually connected directly to a suitable power source, allowing higher rates of fire with sufficient heat dispersal and eliminating the secondary magazine. Pulse Weapon rounds do a great deal of damage on impact, mostly due to the extreme thermal energy of the plasma mass and the speed with which the projectile impacts, which helps ensure that armoured targets are more heavily damaged. The electromagnetic field that holds the charge together flattens on impact slightly before breaking, which causes the resulting impact to spread over a wider area than would otherwise be possible. The speed at which the plasma projectile is launched is so extreme, that in some cases, it has been known to "light the air on fire", due to its velocity being close to the speed of light.
- Codex: Tau (3rd Edition), pg. 19
- Codex: Tau Empire (4th Edition), pg. 29
- Codex: Tau Empire (6th Edition), pp. 66-67
- Imperial Armour Apocalypse (2nd Edition), pg. 84
- Imperial Armour Apocalypse II, pg. 58
- Imperial Armour Volume Three - The Taros Campaign, pp. 80-81
- Rogue Trader: Into the Storm (RPG), pg. 121
- Deathwatch: Core Rulebook (RPG), pg. 366