This is a little trick I learned in my countless hours of playing this horribly addicting, annoying, frustrating and fun as shit game. You unlock weapons and armor in Destiny with XP gains. So the faster you can apply XP gains the faster you can upgrade your gear. This quickest way I found is to Bounty Stack. Turn in as many bounties as possible with the weapons and armor you want upgraded equipped before you turn in the bounties.
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