Yea it is not PER ROUND. For instance my 10mm Pistol does 6 damage, but my 10mm smg does 22 damage. They both use the same ammo. BUT if I target a enemy with the smg and use 1 action point which consist of a burst of ammo. It will do darn near the same damage as 1 action point from the pistol. Here is my take on it.
The smg damage of 22 is considered if every round in a action phase hits. Where the pistol is 1 round per phase. If that makes sense


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