ALI-50 110mm autocannon
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Summary
The 110mm rotary cannons are the secondary weapons of the UNSC C709 Longsword Starfighter.
Ammunition
It is unclear what type of ammunition that is used but it is most likely that the shells are made of Depleted Uranium. Quite effective in close range Dogfights with Covenant Seraphs.
References
First Strike pg 38
