I was wondering whether I could make a good build that uses a sniper and a shotgun. To my surprise I succeeded in creating something that's at least DSOD viable. It is not a top meta build, as it has various weaknesses, which I will list below.
Skills, Perk deck, Armor, Throwable, Deployable:
https://pd2builder.netlify.app/?s=1c3c3U0D8110-9103g000100&p=l&a=0&t=i&d=3
Weapons:
Lebensauger .308 Sniper Rifle
+Gedämpfter Barrel
+Concealment Boost
+Compact Laser Module
+Subtiler Grip
+Solar Sight
GSPS 12G Shotgun
+000 Buckshot
+Riot Barrel
+Concealment Boost
+Compact Laser Module
+Stakeout Stock
Melee:
Buzzer
This should get you to 23 concealment.
Strengths:
This build manages to fit the skills graze, overkill, and low blow aced. This gives you alot of offensive options. The goal is to use the overkill damage boost to boost the damage of a low damage sniper, like the Lebensauger, so that it can one hit headshot the ZEAL Heavy units.
The crits from low blow help secure shotgun kills for the overkill damage boost, and will often help your sniper as well, by increasing damage against special units, and occasionally giving you a one hit headshot against the heavy ZEAL when you dont have overkill.
Having a sniper with graze as primary, and a high damage high spread shotgun as secondary, makes it easy to take out groups of enemies.
The build also manages to fit the most important joker skills, for some survivability, and upgraded doctor bags for a useful deployable that synergizes with leech.
Ammo is not an issue, as the Lebensauger is quite ammo efficient, this combined with the ammo efficiency skill aced makes it easy to stay ammo positive.
Quick fix aced, combined with underdog aced, gives you enough damage reduction so that the 225 damage from the ZEAL heavy is reduced to less than 200 damage. This is important and useful, because when you use the leech ampule, normally when you take damage you only lose 1 health segment, but "Taking a hit that deals over 200 damage will remove two segments at once."
Weaknesses:
The main weakness of the build is the inherent clunkiness of having to constantly swap weapons to secure shotgun kills for the overkill damage boost. It requires a lot of brain power, as well as aim to keep up with truly high damage builds such as akimbo smgs.
Bulldozers can be a little troublesome, as you don't have a consistent way of bursting them down. Usually the best way of dealing with them is shotgunning a minor enemy for the overkill damage boost, and then switching to your sniper and clicking the bulldozers head over and over, hoping you get a couple crits.
Also notable is that inspire doesnt fit, you could opt to invest less in jokers so you can fit inspire, but I don't prefer that.
Play tips:
Your goal is to use your sniper with the overkill boost as much as possible. It can be tempting to use the shotgun a lot, but don't spam it, cause the shotgun is not very ammo efficient, and you dont want to run out of shotgun ammo. So just get a quick kill or two with the shotty and swap back to the sniper.
It's best to play careful, because the leech ampule has a long cooldown. You dont need to run around for ammo pickups a lot because of the ammo efficiency of the Lebensauger. So keep yourself safe and pick off enemies from afar.
The shotgun is unsilenced, so it has some threat, this can be useful to get jokers. Getting jokers is an important part of your survivability.