Caseless autocannon ammunition was developed by the Federated Commonwealth in 3055 to provide more ammunition. Instead of a standard metal or plastic shell casing filled with propellant, the caseless autocannon round had the propellant "packed" around the projectile. This resulted in lighter autocannon rounds, allowing a 'Mech's autocannon magazine to carry twice as many rounds. This feature was particularly useful for the larger bore autocannon, like those mounted on the Hunchback.
Though the caseless rounds were effective most of the time in some notable cases they would jam the 'Mech's ammunition feed system, leaving the MechWarrior in a fight without their biggest gun. The other problem is that the NAIS wasn't able to create a feed system that could handle caseless and standard ammunition. This meant that an autocannon capable of firing caseless rounds could only fire caseless rounds. Given the relative scarcity of such ammunition, and that the cannon couldn't use ammunition captured from other armies, the caseless capable autocannon remains very rare on the field.
Caseless is manufactured on the following planets:
|???||Al Na'ir||Scarborough Manufacturers||???|||
|???||Yeffters Weapons Factory||Gulkana||???|||
|???||Kalidasa||Kali Yama Weapons Industries||???|||
|???||Kendall||Kali Yama - Alphard Trading Corporation||???|||
- Tactical Operations, p. 352, "Caseless Autocannon Ammo"
- Tactical Handbook, p. 53, "Casseles Autocannon"