APS Underwater Assault Rifle (D20 Modern Equipment)
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 APS Underwater Assault Rifle
|Magazine||26 round box|
|Range Increment||(see below)|
|Rate of fire||S, A|
 APS system
The APS (Avtomat Podvodnyj Spetsialnyj, or Special Underwater Assault Rifle) was developed during the early 1970s at TSNIITOCHMASH (Central Institute for Precision Machine building) by the team lead by V. Simonov. APS has been in active service with combat divers of the Soviet and Russian Navy since circa 1975.
The APS is designed for special underwater cartridges, which fire 5.66 mm needle-like projectiles 120 mm long. The projectiles are stabilized using a hydrodynamic cavity, generated by the flat point of the projectile. The cartridges use standard 5.45 x 39 cases, sealed from water. The APS itself is a relatively crude, smoothbore arm, with a gas operated, rotating bolt action, fired from an open bolt. Single safety / selector switch is located at the left side of the receiver and allows for single shots and full automatic fire. The gas system features a patented self-adjusting gas valve, which allows the gun to be fired both underwater and in atmosphere. The simple trigger unit allows for single shots and full automatic fire. The rate of fire under water, as well as the effective range, depends on the actual depth. Sights are crude: a non-adjustable open notch rear and post front. The retractable buttstock is made from steel wire. The most complicated thing in the whole design is the feed system, which includes several parts to avoid double and even triple feed with the extremely long projectiles. Unusually deep (front to back) magazines are made from polymer and hold 26 rounds.
It must be noted that while APS could be fired "above the water", it should be done only in the case of emergency. According to the available sources, the expected service life of the APS when fired "in the air" degrades severely, and the effective range is limited only to several tens of meters. So, the APS is useful only under the water, where it is quite effective.
 Special rules
Underwater, the range increment is 50, above water it is 10.
Due to this weapon's large, bulky magazine, there is a -1 penalty to hit whenever you switch targets. Otherwise, this weapon may be fired underwater without penalty.
It should also be noted that being hit with this weapon will pierce and damage SCUBA gear causing additional effects to divers as the GM sees fit.