Missing Shots?

Not sure. Recording your own gameplay and analyzing it is the best way to determine is your controller sensitivity is too high and your in fact aiming incorrectly.

I play with a controller on pc and i play at 3/3 sensitivity. I would not advise playing on high sensitivity in this game and resorting to jerky snap aiming.

Its all about consistency... And that works better with somewhat slow sensitivity.

Also keep in mind bullet drop and occasionally having to lead targets.

Other then that, not seeing video its hard to tell whats going on.