Tuesday, April 5, 2011

D is also for "Dumb way to handle machine guns"

The post I mentioned in my last "D is for" post...

Fair warning: This may be wrong about the tendency mentioned - it's based on what I remember of one specific game. The trouble is, I can't check any others. However, I suspect that it isn't, because characters in Shadowrun would have had fewer HPE (Hit Point Equivalents), so they would have been dropping like flies.

I've noticed a tendency to treat bursts or sustained fire with a machine gun or similar weapon as one attack, whereas bows treat each arrow as one shot (Which, admittedly makes sense, it's the MGs I'm arguing that should be changed, not the bows). This leads to an interesting problem: Given the same number of rounds used, if those fired by the MG are bursts, then (assuming the characters using them are both tuned to the same extent for each weapon, whether they're experts or likely to hit themselves) the bow is more accurate per round fired. This means, in turn, that a bow will end up being more cost effective per damage unit done. (Because, statistically, it gets more chances to hit. Assuming that neither of them gets a lucky streak in their rolls, it works out. Of course, randomness and luck can't be thrown out, but it should work), and, in fact, do more damage.


The aforementioned characters buy, respectively, two twenty round "ammo holders" (A generic term is used because there are several different things that would work), and forty arrows.

Let's track the amount of hits and damage for each weapon as they go through those:

(Assuming they need a 15 to hit)

Bow (d6 damage)
  1. 20 (3)
  2. 6
  3. 9
  4. 7
  5. 1
  6. 19
  7. 12
  8. 8
  9. 11
  10. 15 (1)
  11. 9
  12. 18 (6)
  13. 12
  14. 7
  15. 4
  16. 16 (4)
  17. 4
  18. 15 (1)
  19. 14
  20. 17 (4)
  21. 14
  22. 13
  23. 7
  24. 7
  25. 12
  26. 6
  27. 6
  28. 11
  29. 17 (3)
  30. 13
  31. 13
  32. 16 (2)
  33. 5
  34. 16 (2)
  35. 7
  36. 1
  37. 9
  38. 6
  39. 15 (2)
  40. 10
Total: 9 hits, 28 damage

MG (2d6 damage)
  1. 11
  2. 3
  3. 15 (8)
  4. 19 (3)
  5. 9
  6. 6
  7. 10
  8. 12
Total: 2 hits, 11 damage

Note: I assumed that each burst was five rounds.

I suggest rolling to hit and damage for each round fired, regardless of weapon type.


The party is fighting four Trolls in a modern/near future game, each of whom can split their fire between two of the available targets. There are three people in the party (Mage, Shaman, Street Samurai.)

To hit the Mage (Martin Troldmand, 12 HP) or Shaman (George Terremoto, 28 HP) takes a 7.

To hit the Street Samurai (Nicole Maiera, 27 HP) takes a 13.

T1 fires a three round burst at Nicole, and two rounds at Martin. Rolling to hit, he gets 10, 5, 4, and then 14, 13. The damage to Martin is 3, 7, leaving him at 2 HP.

T2 fires a five round burst at Nicole. He gets 17, 13, 2, 8, 14. The damage done to her is 10, 2, 4 (Good thing I remembered to check how many hits he got... The next two were 2, 12, which would have very nearly killed her (It requires taking damage equal to your negative HP to kill you on the spot, but she'd have been in bad shape).), leaving her with 11 HP.

T3 fires three rounds at George and two at Martin. She gets 6, 20, 5, and 1, 15. She does 3 damage to George (A critical adds an extra die. In this case, the roll didn't work out so well.), and 7 to Martin (Youch!). They're now down to 25 and -5, respectively.

T4 fires two shots at Nicole and three at George, getting 19, 6, and 12, 4, 7. Rolling damage, he gets 7, and 5, 2. Nicole is now at 4 HP, and George is at 18.

So, one person down and dropping, the fighter-equivalent nearly knocked out, and the Shaman injured. Unless Nicole and George can manage to do some serious damage to the Trolls, they're going to go down in the third round - which would be the shortest combat I've ever seen (This excludes such instances as a dragon against a 1st level party, etc.).

At this point, lets pause and see what this might have looked like using the standard method:

T1 fires a three round burst at Nicole, and a two round one at Martin. He gets a 19 and a 5. Rolling for damage on Nicole, he gets 9. She's at 18 HP, and Martin is unhurt (Just the opposite of above, plus they did less damage).

T2 fires a five round burst at Nicole. He gets 13, and a 2 for damage. She's now at 16 HP.

T3 fires two rounds at Martin and three at George. She gets 11 and 16, with 3 and 12 for damage. This leaves Martin at 9 HP, and George at 16 HP.

T4 fires two shots at Nicole and three at George, getting 19 and 20. Rolling damage, he gets 2 and 15. Nicole is at 14 HP, and George is at 1 HP.

The party is still in better shape overall than they are using the new method.


  1. I see what you're getting at, and I don't want to come in too quick on something you've clearly thought about much deeper than I have.

    I'd say only I feel there's a difference in how a rapid-fire weapon is treated compared with a single shot, specifically that the individual rounds with the rapid-fire weapon may be apportioned less value by the firer, with the weapon treated almost as area-effect, and there being less intention of hitting with each round. The need for less concentration is the pay-off.

    Just some thoughts. As I think I've said before, I'm glad you're taking the time - it's good to go deep into a specific subject on occasion, or read the thoughts of someone who has. We can't each cover everything, but together we can cover a lot. I'll be interested in seeing where this takes you.

  2. What about attack bonuses for bursts, to offset the reduced number of "attacks"? That's the way I did it, and I recall it being the way machine guns work in GURPS, too. The reasoning, I suppose, is that multiple bullets fired in a single burst are fired too quickly to be individually aimed, and the gunner is struggling just to keep the gun aimed in the same general direction. But putting more lead in the air should affect the chance of hitting. A repeating crossbow should work in roughly the same way, rolling once in one combat round for all bolts aimed at a specific area.

    There's also the idea that machinegun bursts should be area of effect attacks, possibly hitting targets a couple feet to either side or behind the intended target. When I suggested some gun rules for OD&D, I forgot about that, too.

  3. @Porky:

    Into the depths of game design, I suspect.


    Possibly. That's a good thought. I might also want to think about raising the damage a bit, or at least making it D12 (Since criticals add another die of the same type). I'll think about this more as I go.