The sad irony is, in order to do the nerf Paul had to get permission from Russ, after making a case about how autocannons are just obscenely overpowered.
O.o; Russ might be the one that needs to go. He wants autocannons that do lots of damage in a single shot because it looks cool.
Meanwhile, the lore is that they are automatic and burst fire weapons that fire -- and mind you not just one but MANY -- tank rounds until sufficient rounds are fired down range to meet the damage rating. So they would look even cooler while being much easier to balance due to not being max upfront damage anymore.
Inner Sphere's largest Mech or Tank mounted AC/20 is the 4 shot Chemjet Gun (TRO-3026), 185mm at 5 damage per shot.
What MWO is featuring is "
Rifles", the obsolete technology ditched and dumped because a single shot modeled off of old tanks couldn't do jack. The one Heavy Rifle I found in lore is described as "190mm." It fired a single shot, took a while to 'prime' to fire again, and does 9 damage. However, against 3050 military grade armor, it only does 6 damage. It happens to weigh 8 tons.
Meanwhile your average AC/5 is between 40mm (that's 20mm above mech-mounted machine guns) to a maximum recorded (so far) size of 120mm. That 120mm AC/5 is the GM Whirlwind/5 (Hunter ridge & Wolves on the border) and is described as a 3 shot burst to deal 5 damage (each shot dealing 1.666666666666667 damage).
That's 3 shots of
this, having to hit one place, to deal 5 damage.
The AC/2 ranges from 30mm (10mm higher than an MG) to 80mm. Here's a middle ground at
40mm.
Now mind you, the 'ammo count' is not an actual count of the individual bullets but of the 'uses' it has. More specifically for the burst fire sort each 'payload' is loaded in a cassette (magazine) that is ejected after its emptied. In the GM Whirlwind/5's case a ton of ammunition (since source gives '15' units when MWO gives 30) would have 15 cassettes and thus 15 uses of the AC/5. Considering each 'use' is 3 shots you'd actually have 45 rounds per ton. In another case with the Imperator-A 80mm AC/5 (Price of Glory) it's a 5 shot automatic-fire gun with each 'shot' doing 1 damage. If it were a burst fire, it'd have 15 cassettes, each cassette would have 5 shots, for a total of 75 shots. Since it's a chain fed automatic, it simply has 75 shots per ton and an AC5's 'cooldown rate' is how long it takes to make 5 shots.
If you're wondering what AC/20 requires a 100 shot burst, it happens to be the Victor's Pontiac 100.
As for the AC/2 that requires 10 shots? Whirlwind-L AC/2 (
30 to 32mm) on the Blackjack-1.
So with a glimpse of that, how powerful are 20mm machine guns? Well while people frequently refer to the Gau-8, that is unfortunately incorrect as that's an AC/2 sized weapon at lighter tonnage (got to remember the barrels for AC/2s are huge and long and half the weight of the weapon system, plus feeding plus ejection and then component materials and so on). Well here's a
glimpse. That's the correct caliber. Ultimately, an MG managed the same damage as an AC/2 in 10 seconds from source (that being 2 damage), but unlike the AC/2 which had to stop and cool and reload the machine gun could squeeze off non-stop. Its range issues had to do less with recoil and more with the fact that in the books they are tilted downward at the ground so that the pilot could fire them without even paying attention to what he's aiming at and keep his wits about him for real threats.
But that's...just a rant from someone sick of PGI spitting on the lore. We don't have SRMs in MWO, we have glorified short range MRMs SRMs have soft-locked guidance and chase after NARC beacons! Why the heck do you think the Kintaro or the Raven 3-L have NARC? To mark enemies for LRMs? Pfft as if! It's to mark enemies for their SRMs!!
...Sigh.
Oh well.
Sadly Russ can't go. He's the CEO of PGI.