Weird Rank Ups

[C-Y-F-E-R]

I have seen some profiles were the weapons are ranked up without using them not even a single kill/usage but XP in millions.

how can this be possible and these guys are like 20+ MR 

Edited January 3, 2019 by C-Y-F-E-R

[(PSN)abbacephas]

Passive affinity gain. You equip the weapon but never use it.

[(XBOX)ShadowBlood89]

Warframes and weapons gain Affinity for several types of actions, detailed below. Unless specified otherwise, all Affinity gained uses the split according to the general rule: 25% of the amount goes to your Warframe and 75% of the amount is divided evenly among all equipped weapons (25% each for three, 37.5% each for two, or the full 75% if only one is equipped).

• Kill an enemy with a Warframe ability. All of the Affinity goes to the Warframe.
• Kill an enemy with a weapon. Half of the Affinity goes to the Warframe and half to the killing weapon.
• Be near an allied Tenno when they kill an enemy. When within 50 meters of an ally when they kill an enemy, you gain the same total Affinity, distributed according to the general rule specified above. This doesn't reduce the Affinity gained by the killing player, and doesn't reduce the Affinity gained by other nearby allies. This applies to Archwing mode with much larger ranges for shared affinity.
• No weapons equipped. All of the Affinity goes to the Warframe.
  • This applies when the only equipped weapons are overridden by ability-created ones. (E.g. Using Exalted Blade while only having a melee weapon equipped.)

[XRosenkreuz]

Old Draco, or more recently, Onslaught. With a booster, you can get a weapon from 0 to 30 in, I think, 8 rounds in Elite Onslaught without ever actually using it.

[16Bitman]

12 minutes ago, XRosenkreuz said:

Old Draco, or more recently, Onslaught. With a booster, you can get a weapon from 0 to 30 in, I think, 8 rounds in Elite Onslaught without ever actually using it.

With a booster you can get a weapon to rank 30 by zone 2 if you have a DPS in your squad.