>calling it a logistical breeze when there's no indication is because it's fictional and apparently we shouldn't listen to anything gw says
Giving an outline of a vehicle or weapon's capabilities is not the same as giving actual numbers, especially when the numbers are totally contradictory. These are the same dipstuffs that said that the land raider has something like 300mm of armor, even though that is completely and totally contradicted by just about everything.
also you'd be surprised how large a 120 mm barrel is
An M1 abrams has a 120mm gun.
Compare the size of the people in the top hatches to the barrel diameter. You could stick your head down a Lemon Bus gun.
Not so with the Abrams. It's obviously larger than 120mm.