POW. Sniped!
Beretta is a GUN, with a massive hit bonus and conditional post-shot effects. The former means it's great for the many 3 characters in the game, the latter still means that without some additional help then you wont be fighting like a or anytime soon.
- So, the big downside to Beretta, on one hand you need to beat a fight by 2 to even get a second shot, or you can have the hit deal 3 damage, or you can beat by 4 to get both effects. On Standard this means you need to aim for a big number like +9 or +10 if you want to guarantee bonus damage and/or bonus shots, and you need to push all the way to +11 or +12 to be high enough over 3 and 4 fight foes to get guaranteed benefits.
Knowing the above, a +4 to the fight test, to net most characters who like guns in the first place, a +7 base. Shooting at +7 is quite alright, if you want to land a single 2 damage hit. You can do that with a lot of security against regular ol' 2 or 3 fight enemies like Acolyte, but the fact that you have such a weapon in your hands at all -probably- means that you're hunting bigger game, it's probably your job to put down the 3 health chaff and the 4-5 health minibosses, and to chunk down the 10+ health big bads. For this job the impressive +7 fight actually becomes annoyingly flaky, bad hits that leave you with a living enemy and/or an exhausted gun, all of a suddent your only venue to killing the target is gone and the team is in trouble!
So, obviously, Beretta M1918 synergizes with statistical boosters like Well Connected, Hard Knocks, High Roller in particular is a natural combination since both cards really reward you for gross overkills, along with Lucky Cigarette Case to cash in on all the overcommits and similar effects. Perhaps less obviously, This gun synergizes with , as a means of reorienting yourself when a bad token pull would leave you stranded, someone like Winifred Habbamock or Finn Edwards is almost certainly going to get better results with a Beretta than a Tony Morgan.
If you compare Beretta M1918 to the Chicago Typewriter its's an excercise in splitting efficiency hairs, but once it's all boiled down, a Beretta far outpaces the Chicago Typewriter as a means of fighting when your starting is 3 or less and you're not using many boosts or depending on something incidental, but the flankyness of the Beretta makes the Chicago Typewriter straight up better when you have a higher starting point and/or building easy access to static boosts.