kinda WIP, don't have all cards yet
With Shotguns (I prefer the AA12) you have to get a little closer, so Breakout is really nice.
As soon as you have a good Shotgun primary you can replace the Belgian sidearm if you want, but remember, the most cards support the Shotguns in this deck.
Since Mom already has a revive I found the support cards nice if someone is downed, so even if the insta revive is used up you are still the quick reviver (if there is no Doc or dedicated healer) while the rest can cover your back.
Silver Bullets can replace Combat Training when you play in a team with friends so you can drop money for the group upgrades which costs 1500. Else it's safer to safe up some money.
PS: fair warning about penetrating bullets -> watch out for doors with alarms when you shoot the Ridden