Talk:Affinity/@comment-67.242.2.4-20130505015305/@comment-70.138.216.163-20130519064128

yes you cant lose Mastery Rank by selling the item and  losing all teh levels in that weapon/warframe. However, if you decide to buy the same weapon/warframe, you will not gain any Mastery points for the levels you have already earned with that weapon/warframe. This is to keep players from buying a gun, maxing it out, selling it, and then buying it again for endelss Mastery.