When I pop in a full 30 rounder pull back the charging handle and let go usually the first couple rounds get pinched between the mag lips and the bolt lugs in the chamber opening. I saw a Colt and the bottom two lugs were more like ramps to assisit with the round entering the chamber.

Would it be a bad idea to dremel the two bottom lugs a little so they would not be so sharp and let the round slid into the chamber better?

Sounds like you may need to polish the feed ramps.  Just smoothed out a little, not really removing any metal.  Also chek to make sure the mag is fully seated, sometimes a full 30 on a closed bolt takes a good slap to the bottom of the mag.  HTH

I recently had a bad mag that caused this same malfunction.  It seems that the back corner of the feed lips were misshapen, causing a full mag to point its rounds slightly downward and straight into the lugs.