And that's because FASA is retarded. I say inexplicable lack of heat, because I guarantee you that even the most fantastic bullshitter in the world couldn't come up with a single reason for them to generate less heat than an AC-10. It just contributes to it being the EZMode weapon that it is. It doesn't even have the minimum range it's supposed to have. Why do you think the Timberwolf B is such a rapetrain? Because it can alpha the fapp out of anything, and then dump a ton of extra damage on for free. This is why they were considered more cheese in tabletop than any clantech weapon was.
Especially considering that they aren't terribly expensive in MWLL, go ahead, give us the mechlab - let me recreate gausszilla. Especially considering that they seem to be Heavy weapons, not Assault. Theoretically a Timby could carry four of them.