I am completely new to ARs and am still climbing the learning curve so please be patient.  I have been shooting Lake City M193 with resonable results.  I own a DPMS 20" HBAR, non-chrome, flat top and want to know a good bullet wieght (62 seems to work well also).  I also, when I get the cash, want to upgrade (chrome bar, dual stage trig, etc) Any suggestions please.  Thanks.

First off Welcome :)

M193 is God's ammo IMHO the only other ammo that I want is IMI's M855 when I see it available again.

As to Barrels. I have an HBAR on my post-ban and it has served me well but on my Pre-ban it's Government profile all the way. Much lighter. Actually I have the pencil thin Gov profile and the standard A2 gov. The pencil thin is nice and light but heats up really fast (obviously) and even though accurate is not my fav of the 2.

Good luck with your new rifle and check out the Ammo board on this site to get more indepth detail. There is a wealth of knowledge to be had here.