... frankly, I’m not quite sure where this is going, because I’m still fumbling my way through the idea and trying to step back from my own AU’s assumptions so I can look at things through BT eyes again. I suppose I’m coming at it more as an ‘evolutionary line’ sort of thing, as a step up from Rifle (Cannon)s... but also from the assumption that all weapons have ‘realistic’ ranges in-universe, not the short ranges that are gameplay- and hex-friendly but irk so many people. (For instance, ACs would get 10x their base range, so the ‘snub-nosed AC/5’ hits out to 120 hexes/3600m or so. Energy weapons top out at about 10-15km for a variety of reasons, with some damage drop-off at extreme ranges, but that’s still effectively LOS.)
Say the first autocannon was this six-ton/short-ranged AC/5 — after the Light R(C) and Medium R(C), it looks like a major step up. Then, say fifty years later or so, the ‘proper’ AC/5 comes along: two more tons of mass and the added bulk is a good trade to make for 50% better effective range, yes?
@ YingJanshi: ... sort’a-kind’a, yeah, except the LACs are still as heavy as the original Ack-2s. At least at Tech Level D; at TL-E, the weight and bulk would start dropping again.