Offered for sale or trade is a used, but not abused, Colt upper. I acquired this upper from another forum member and have no idea of the round count, but as soon as I acquired it I cleaned it (It had not been cleaned for a long time, if ever) and sighted it in at 100 yards. The sight-in target is below. The first impact was at 1 o'clock and progressed from there until the last three were near the center diamond. There is a small mark on the right side of the barrel near the muzzle, and a place on the rear sight housing that appears to have been rubbed against something painted white. This is a large pin upper which should fit nearly any lower except the small pin Colt lowers. There is no flash suppressor nor bayonet lug (neither of which affected the utility for me) on the 18 1/2 inch barrel. I'm not sure of the twist, but accuracy was excellent with 55 grain M193 GI bullets. I'm asking $400 OBO, or trade for a like-valued optical sight + $, FTF in the Portland area. If you want me to ship it, it's on your dime. If you want to low-ball me, I'll respond only if the offer is in a PM. Any low-balls on the thread will be ignored. This is a good, economical upper that should provide many years of enjoyment and utility.