Ever play the 2.2 version?
Fire off a M249 SAW and grab 10d20. You only hit on like a 1-4 (with a good skill level), but any bullets that miss the primary target then roll against the next target in the line of fire, then the next, then again against the next, etc. until all of the bullets either hit something/someone or there are no targets left in the path of fire. A character could get off three of these attacks per turn, so the dice rolling was obscene.
We once had a character fire of a M19 AGL (automatic grenade launcher) and he grabbed his 5d20. In addition to the above he had to calculate scatter from one round to the next and then calculate blast effects and fragmentation hits to all targets in the blast radius. It took an hour to calculate the effects of that one action, and he still had the ability to fire off a second such attack in his turn. The joke in the group became that, if the players wanted to take a food break, have Mark fire off the M19.
I think it was 10d6 not d20 or am I screwing up my versions? I thought the damage was always d6's but the skill roll later used a d20? I had all versions but I don't think I actually ran a campaign with 2.2. I hated all of the fists of dice also, so I had a simple house rule starting with version 1. A weapon with a damage of 10 would normally roll 10d6, for example. I instead had the player roll a single d6 and multiply by 10 for damage. While it made the curve flat, it still had the same damage range.
Mk or "Mark" 19, not M19. I've fired those in real life and it was the most awesome gun experience ever. You push the butterfly trigger down for a 6 round burst. You see little black tennis balls fling through the air. A couple seconds later, grenades are exploding all over down range. Very cool. Except for the time an idiot fired a round into the dirt in the dark about 20 meters in front of my Hummer while I was up in the turret playing assistant gunner. Stuff dinged off my kevlar and I thought I got a piece of shrapnel in my cheek until I pulled it out and it was just a pebble.
Sorry nostalgic moment.
All of those d20s were for the roll to hit (rolled per round fired!). Damage and hit locations were yet more rolls. IIRC, Version 2.0 used d10s instead of d20s but was otherwise the same.