Sometimes to get them fixed you need to put them in the hands of someone more experienced so that he can see exactly what is happening. I have found that new ARs very often need a TON of lube to function well. I have "fixed" several of my buddies AR's who thought that it they get dirty if they lubed it too much. The AR will get cruddy whether there is lube on there or not so you might as well lube it up. After about 500 rounds you shouldn't need as much lube anymore and things will get better. I have only owned one AR that didn't jam at all when I first got it. It was a cheap Double Star.
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