Below is the hit location table for OHTAS Traveller. Note that this has been modified from the T5 to balance the hit probabilities correctly between appendages*, increase the chance of a graze**, and decrease the chance of torso.
Hit Locations (1d6-1d6):
Roll Location Probability
-5 Torso (2.8%)
-4 Head (5.6%)
-3 Arm L (8.3%)
-2 Leg L (11.1%)
-1 Torso (13.9%)
0 Graze (16.7%)
1 Torso (13.9%)
2 Leg R (11.1%)
3 Arm R (8.3%)
4 Head (5.6%)
5 Torso (2.8%)
Total Probabilities:
Head 11.1%
Arm 16.7%
Torso 33.3%
Leg 22.2%
Graze 16.7%
*T5 gives a higher probability to Right Arm or Leg (11.1%) than Left Arm or Leg (8.3%).
**This draws a little abuse away from the torso and makes highly accurate shooters a little less deadly.
Some comments on the rationale for this...
The T5 table was, as I mentioned, is kind of messed up with higher hit probabilities for Right Arm/Leg (11.1%) than Left Arm/Leg (8.3%). Also, the highest hit probability in T5 is Torso at 44.4% and the lowest is Head or Graze at 8.3%. Total probability in T5 is the same for an Arm or a Leg hit at 19.4%
It obviously didn't make sense that right arm/leg should be any easier to hit than the left. It does kind of make sense that Torso should be higher than the rest, but 44.4% seemed a little too high.
My constraints on rebalancing the table were:
1. Left/Right Arm should be the same probability
2. Left/Right Leg should be the same probability
3. Probability of a Leg hit (left or right) should be higher than the probability
of an Arm hit (left or right).
4. Greatest probability should be Torso.
That leaves you with only a few ways of re-arranging the numbers for the other hit locations. I opted for putting Torso at 33.3% which was, per constraint 4, higher than any other location, but more reasonable than the T5 44.4%. That basically left me with only two other numbers, 16.7% and 11.1% for either Head or Graze.
I opted, kind of arbitrarily, for putting Graze at 16.7% and Head at 11.1%, figuring we'd just see how it worked. I think the possibility of a hit with no damage adds a little something to the game, but I could be convinced to swap these probabilities.
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