Since I am not a metallurgist those small things are important.A guy was at the range and his AR quit.Someone pulled the BCG and it had disintegrated.Definitely inferior metal but it was greek to me other than it was broke.Dont know what broke but I certainly would not want that to happen cause to save a few bucks I bought a POS.Thanks for the info.The barrel and BCG are what is confusing me.buy or save and buy better
This is definitely where you don't want to skimp on an AR...check out my post above and buy a BCG that has those things...Palmettos premium group fits the bill and isn't as expensive as the BCM...but BCM would be my choice.

