Agianst some of my freinds advice, I purchased a NIB 6601. I got it with a scope and extra 30 round Colt mag for 800.00, hope I did good. My question is, how do I properly break in the barrell. It appears that the chamber is chrome lined, but I do not know about the bore itself. It's my first AR, so all the help I can get would be appreciated.

You got an excellent deal.  Clean it a lube it well according to the manual, then go shoot it.  IMHO, breaking in a barrel is unnecessary unless it is a high quality match barrel.  If you take care of it by keeping it cleaned and well lubed, it will take care of you.  Enjoy your AR.

i have a mt6601 also, the chamber is chrome but the barrel is not. i didnt go thru a 'break in' period. the only thing i did was avoid the "metal" bore brush for a while, just nylon. after 200rds or so i went to the bronze brush. my 6601 works like a charm. enjoy~~
CB

Thanks for the replies, but I do have another question. I have a 1 piece free-float handguard, well actually it is the handguard and the barrell nut, but it appears that the front site/gas block is going to have to be removed, and also the original barrell nut to install this one. Is this something that I can do, ot do I need to go to a gunsmith?