Pinpoint

Pinpoint is a campaign Commendation in Halo: Reach. A point is obtained every time the player kills an enemy with a headshot during the Campaign. The Commendation is represented by a skull with a target on its head on a green background.Bungie.net: Halo: Reach Career Stats
===Requirements===
Kill an enemy with a headshot during the Campaign.
Tier 	Required #	Rewarded Cr
Iron 	50 	100
Bronze	250 	750
Silver	500 	1000
Gold 	4,000 	2000
Onyx 	8,000 	2000
MAX 	20,000 	0
===Easy Way to Get Pinpoint===
Go to the level Nightfall on at least Normal difficulty and get a checkpoint just as the first elite of the level comes into view. It may take a few tries, but positioned correctly you can get a headshot with little or no movement of the reticle. Snipe the elite then go to the start menu and press Return to Previous Checkpoint.
==Sources==