Read Simon Kent's post for details.

Fix will be released in next update. Thanks for report!

Will be added in next update

Check my comment at getlocalization site :)

Battlelog featured description for every weapon for Battlefield 3. This is not the case for Battlefield 4 sadly. As you see on Battlelog, there is only description for some of the items. 

Work in progress at the moment. I am going to investigate more the coming week.