so i was watching on youtube how to take apart the m16, so today i totally took that freakin gun apart and put it back together with no problem.. then i realize that the outter barrow was lose to i decided to take the top off again to check it out.. i found that it was just acouple of loose bolt on the outside that i didn't even have to take the gun apart for.. then my curiousity got the best of me.. i pulled the hop up cover lever just to see how it works. then the whole thing just feel apart and i've tried putting that sucker back together about 50 times already and i just cant get it right. help me.