Since I'm not sure if Moosegod is going to be around to check his emails (and presuming he might pop in here once or twice while doing the Thanksgiving thing), I wanted to throw this up and get his and everyone else's opinion. I never realized that Shadowrun didn't have any underbarrel shotguns in the game, and it seems like a good addition for our types of character; the assault rifle is for long-range and heavy-enemy fire, while the shotgun is good for up-close and personal combat (not to mention paranormal critters).
So with that in mind, I used the Cannon Companion to fandangle the following using the Shotgun frame. Lemme know if it sounds good.
ARES M46 "MASTERKEY" (Underbarrel Shotgun)
The Masterkey (photo) is a shotgun designed to be used as an underbarrel attachment on assault rifles and machine guns. While it has a limited magazine size, the unique side-by-side double magazine of the Masterkey allows its users to load the weapon with two different types of ammunition (typically buckshot and slugs) which they can switch between with a Simple Action (or Free Action if smartlinked).
The Masterkey has a max choke setting of 6 and its range is reduced to 0-9/10-18/19-45/46-90. It takes 3 Complex Actions to remove or attach the Masterkey to a weapon with an underbarrel mount, and it can easily be exchanged with underbarrel weapons of all other standard Ares firearms. The extra weight of the shotgun functions as an underbarrel weight, providing one point of recoil compensation to the attached weapon.
The M46 Masterkey cannot mount any additional accessories. Like other underbarrel weapons, the user can default to using the Masterkey with their default skill with only a +2 TN modifier.
Design Features: Barrel Reduction, Easy Breakdown (used it for the underbarrel attachment rules), Improved Ammo Capacity -2, Improved Concealability 1, Increased Power 2, Selectable Magazine, Underbarrel Weight, Weight Decrease 6.
Quick-Stats: Conceal 6 (on its own, as an attachment it reduces Concealability by -2), Mode SA, Ammo 3(m)/3(m), Damage 10S, Weight 4.35, Cost 2,260¥, FCU 0