I know its been over a year-and-a-half since all this discussion. Reading through it again, I am very confused about what the final decision on all the above. Would someone please explain the final ruling so I can make sure it made the optional rule table correctly. Gads, I'm getting too old for this lol.
Why not just use the rules as they are written for this? Machine guns, throwing lots of dice are going to score lots of hits and have the chance of scoring multiple penetrations. If you score multiple penetrations in a single attack then you only roll one die on the damage chart but give a plus 1 for each extra penetration. So a bunch of machine gun hits in one attack would negate the -2 and give the chance of a killing blow.
I plumb forgot about this. I was using ROF 1 versus machines. With your rule machine guns alone will not bring down a undamaged tripod but once damaged becomes increasingly vulnerable if the machine guns keep hammering away or if heavier guns ding their armor. I'm going to use this in my next games.
Based on the Mr Washburn's description of Martian metal (many small scales or flakes consolidated) effectively, the HMGs "chew through" eventually and then the fun really starts. With lots of bullets hitting, some will likely hit the same place.
Then, big projectiles ricocheting around inside a closed space are really BAD.
My group just uses a D6 for damage rolls on anything that has the Tripod Damage table. Easy Peasy. Think I put this on the Stat Cards, too. You'll usually just get to plink away at the armor unless you get multiple hits. Algebra and negative modifiers make my head ache (and other locations). We have found human players now use rifle and MG armed troops picking on damaged tripods due to the fact its a D6. Many roads to get to your effect, your choice which one you want to use, right? Respectfully, Gunny