Infinity Ward has stated on Reddit that, after seeing fan requests, they are going to add Weapon Mastery Calling Cards to Call of Duty: Modern Warfare.
Weapon Mastery calling cards were previously in many Call of Duty titles, including Call of Duty: Modern Warfare 2.
Infinity Ward Art Director Joel Emslie replied on Reddit confirming that they’ve now put this feature into development and that it will be released soon.
In visual development now. Then into art production. Then hooked up and scripted. Then testing. Certified. Then pushed out in a near future update. No ETA but we are working on them now.
As noted in the above message, it’s just begun in production, so there’s no ETA for this feature. But fans who’ve wanted more ways to master weapons and unlock more items through gameplay now have Weapon Mastery Challenges to look forward too.
Thanks @TheMW2Ghost for the tip!