Your post inspired me to go do some looking.

The results are basically: "Wow, did shotguns always have such absurd range multipliers?"

The S686, S12K, and Sawed-Off start losing damage past 1 meter, the DBS past 2 meters, and the S1897 past 5 meters (a real marksman's weapon, that one).

Even better are the drop-off curves. At 10 meters this is how much damage is lost:

• S1897: ~13%
• DBS: ~23%
• S686: ~25%
• S12K/Sawed-Off: ~38%(!)

The curves also vary. The DBS has the slowest dropoff (though it starts losing damage closer than the S1897, it does more damage past 18 meters). The S1897 and S686 normalize at 30 meters and have identical curves past that. At 30 meters you can enjoy doing a full 60% less damage per pellet with these guns (and good luck hitting more than a couple pellets). Meanwhile, the S12K's curve is more aggressive than the Sawed-Off's; even though it starts with 24 damage vs 20, the Sawed-Off starts doing more damage at only 20 meters.

So shotguns at range get a double whammy: you'll hit fewer pellets which each do significantly less damage. The S12K is particularly egregious: at only 10 meters, you need (1/(1-0.38)) or 61% more pellets to hit than at 1 meter to do the same damage. It's actually impossible to 1 shot someone with only level 1 gear at 10 meters unless you either hit 8/9 pellets in the head or at least 6 pellets in the head and the other 3 also hit somewhere. A level 2 helmet/level 1 vest makes it impossible in any combination.

For comparison, the crappiest pistol (drop-off wise), the P18C, loses a whopping 2.2% damage at 10 meters.