Caseless AC/20

While caseless ammunition has become relatively well known (albeit rarely encountered) as a special munition for existing autocannon, some early attempts at developing this technology involved purpose designed systems. The principal of caseless ammunition is that the propellant is caked together as a solid that contains the round to be expended rather than having a case that needs to be extracted and ejected. This reduces the mass of the ammunition thereby allowing a unit to carry more rounds. This technology has always been problematic however. The weapon vents propellant gasses as it fires and from time to time this can set off ammunition in the weapon ready to be loaded. While the ammunition bay itself is protected from this, the ammunition in the weapon remains vulnerable. In these early systems a failure resulted in a detonation rather than a failure to feed as encountered with later caseless ammunition refits to standard autocannon. It is uncertain if any examples of early dedicated caseless autocannon were ever actually produced and/or if any still survive. As such the existence of this system borders on the mythical and their inclusion as a distinct system in this reference is largely a footnote in the documentation of technology in the 31st century.

Availability
As it is unknown to what extent these early systems ever ended up in production, the term "availability" should be taken with a grain of salt. Nonetheless, at the time of their development the main Successor States listed here each had, at the very least, a technical understanding of these systems.


 * Capellan Confederation
 * Draconis Combine
 * Federated Commonwealth
 * Free Worlds League
 * St. Ives Compact

Game Rules
This system was published in the Tactical Handbook but not mentioned in Maximum Tech. Caseless rounds reappeared in Tactical Operations as a specialized ammunition type, but was not listed as a distinct weapon. Tactical Operations does however mention that the feed mechanisms for caseless vs cased ammunition are incompatible and an autocannon set up to feed from one cannot feed the other. As the stats for Caseless AC/2 and AC/5 are identical with their non caseless relatives, perhaps this is why they were treated merely as a ammo type. The stats for the Caseless AC/10 and AC/20 however do differ slightly in being slightly smaller than the standard type. As this weapon was not referenced in later publications they should not be considered tournament legal and border on being apocryphal.

In BattleTech play, any time a 2 is rolled on a to-hit roll the vented propellant ignites the next round in the feed mechanism, destroying the weapon completely and doing damage to the internal structure of the location on the firing unit that the weapon is mounted equal to one hit from the weapon. Critical hits to the firing unit are rolled normally.