I just noticed this that Paulson’s Revolver had the shotgun feature as I call it. A sneak attack with the terrible shotgun, metal blaster, Paulson’s and perhaps other will do critical damage for all bullets/ beams who hit. Three requirements, you have to do a sneak attack, you have to get pretty close because of spread and you can not use VAT.
Upside is extreme damage; Thinking of switching load out to gauss rifle, Paulson’s Revolver, novasurge and vengeance. Each has its purpose; sniping, sneak attack, VAT and pure damage.
Paulson’s Revolver is lighter and does more sneak attack damage than metal blaster, downside it less standard damage and higher spread.
I never really worked out the pellet damage and range etc, but I do remember Paulsons revolver took chunks of health out of the bullet sponges fairly quickly, and try it out over medium range as well, the pellet spread didn't appear to be that bad and it still did a good 'chunk' damage per shot over a little bit of distance. Novasurge was nice in VATS, perhaps a bit too nice with high EW skills and items that buff Action Points!
If you've been on board zeta and have those guns then you might also have found the electro suppresor as well, that will make the bullet sponges very easy to kill!
My Zeta weopon of choice though is the Atomic Pulvorisor, no where near as powerful as the others but weighs only 2, fairly good for ammo as long as you looted everything on the spaceship but the main plus is it has a very very low AP cost in VATS. If you looted and bring back all the alien weopons then you will have plenty for repairs as well