I recently completed all the challenges for the Vector, but in the match summary I only got 750 operations xp for completing the nick of time challenge (was the last one I needed), but nothing about the mastery. I did get the gold camo though, but I wasn't sure if I got the xp. Is it supposed to be in the match summary or show up as an in game alert?
The first time you complete challenges it shows up at the end of the match summary, showing xp and what you unlocked, it does also pop up on screen during a game if you complete a challenge as well. To double check to see if it did unlock you could always have a look at the weapons challenges and see how complete they are.