Are you comparing a new DPMS to a used Colt when you talk about racking the charging handle? Have you disassembled, cleaned and lubed it yet?
Don't get me wrong, Colt is the higher quality of the 2, but plenty of shooters use DPMS without a problem, me included. Get out there and shoot it! Once you get some rounds through it and break it in, it will feel smoother.
NRA Life Member