The CX-9 is only useable in Survival mode at present, and cannot be taken into Multiplayer or Warzone until the update Having played with it a couple of games, it is not only really fun to play with, but also very rewarding, especially in smaller maps where space is tight. A unique weapon among others, the R1 Shadowhunter allows players to retrieve discarded bolts that have been fired, whether they hit their intended target or not.
Longshot kills are kills from around 30 metres or more, I would recommend getting in ranges of the higher 30’s or early 40’s to guarantee a longshot kill. It will be purchasable through the COD shop or unlockable after completing an in-game challenge.