Ranged weapon damage

Does anybody know the damage values for the guns in the game? It's still a matter of confusion for me. For example, I thought that the Eye of Reach did around 70-80% of damage, however yesterday I had an encounter that required 3 shots to kill. In the VERY same battle I required 1 shot and 1 cutlass hit to kill a FRESH spawn (Yes, I was spawncamping a galleon that attacked us). My friend also has the same issues with the pistol, sometimes its 2 shots, sometimes its 3 shots. Thanks in advance for any detailed explanations how this stuff works because I can't get my head around it.