"Unlock all xbow parts" - 20G

You will need the following to be able to obtain this achievement:

DLC: Aftermath - 1200 MSP

You will not be able to play with the xbow straight away, you need to complete an assignment.
"Sticks and stones"
Win three rounds of Scavenger.


Once you complete the assignment, you need to complete additional 5 assignments in order to unlock all of its parts.

Scan bolt
Is Ok To Thank Me - Get 20 spot assists, designate 10 vehicles, get 1 designated assist.

BA bolt
Stay Away From My Tent- 50 sniper rifle kills and 10 headshots with a sidearm.

HE bolt (two assignments)
Archery 101 - Get 5 kills with the Xbow; and A Good Demo Man - 5 kills with each of the following: hand grenade, underslung grenade launcher and C4.

Xbow scoped
Go Play Close Quarters - Total 150 meters of headshots with sniper rifles, assault rifles, and carbines. (Sounds worse than it is, will come eventually by just playing)

Once you have all parts, or bolts, you can change bolts by pressing D-Pad down!