or am i just being picky. i got 2 bushmaster barrel kits from gunsmoke( and no i'm not flaming him and have not called him cause i want to see if this is normal). the problem is that on one (and maybe the other but i dont know cause hand guard cap is in the way and punches are at work so i can't get gas block off) the back of gas block ( both are shaved gas blocks) is bare metal with a little rust and is also bare on the barrel between the gas block and before it steps up (about a 1/16 but probaly more under gas block). then on the other which is a fluted 20" the finish on crown (my old bushie i bought 2 yrs ago had no finish on chrome part of crown) is in the bore at the edge on one side. plus gas blocks have a good bit of grit in em which i guess doesn't matter cause gas will blow it out if its in barrel port too. what keeps barrel port from rusting too bad?  first time i've seen the barrel off so maybe it is normal. thanks for reading my anal retentive post. please reply so i can either call gunsmoke or bushmaster or put these on uppers. the free float tubes from gunsmoke were kick ass though.

yeh but the whole back of gas block is unfinished.
thanks