Wound allocation doesn't work as it is supposed to in some scenarios. I will try to explain it to you Rufus
Scenario 1. Ten Marines with bolters vs ten Marines with bolters.
10 shots, hit 7, wound 4, four models make saves, the player who has been shot removes any three models. That is nice and simple.
Scenario 2. Ten Marines with bolters vs three marines, two with bolters, one with a special weapon
10 shots, hit 7, wound 4. Wound allocation funtime. You allocate wounds per group of identical armed models. Eg in this scenario you can stack 3 on the bolter guys and 1 on the special weapon, or two on the bolters and one on the special weapon. Spare wounds do not transfer from group to group. So if the bolter guys fail 3 wounds, the spare wound is lost.
Scenario 3. Ten marines, plasma cannon, plasmagun and bolters vs five marines, 1 with plasma gun, and 1 sergent.
This is a more likely scenario and can get complicated fast.
Fire plasmacannon first [as it has more targets to hit at this stage] and hits 5, wounding 5. Plasmagun wounds 1, the other marines bolters inflict say 4 wounds.
So you now have 6 plasma ap2 wounds, and 4 boltgun wounds at ap5 to divide between the 5 models. However, there are three model groups which makes this complicated.
You could for example. stick all 6 plasma wounds on the three bolter models, and put two boltgun wounds on each of the special weapon and sergent, meaning the two more valuble squad members could survive! Notice if you didnt fire the bolters, you would have killed the whole squad
Also if the five man unit didn't have different types of models, they would also all have been wiped out, regardless of the bolters firing or not.
That make sense?
