OK. I am going to put together a simple little build for my first go round. I am going to buy a 300 whisper HBAR for an AR build. Most of these I've seen have no chrome lined bores. Any idea of who could chrome the bore for me? Secondly who is a good person to get to put on my sights and head space and all that cool jazz. I don't want crooked sights. I ultimately am going to build this 300 whisper in the same fashion as Bushmasters dissipator. So I'll have to put a chopped front sight in place of the original and have someone install a new front sight at the right place to fit full length handguards.... so the name of a good person to do that would be appreciated. And the chrome thing. Every thing else will be aftermarket. I'm starting with a Bushmaster lower. Not trying to start a debate but I'd like to hear who makes a damn fine bolt/carrier group and upper reciever.  Other than the (In My mind at least) the big three (Bushmaster, Armalite, Colt). Who has top quality that this newbie might have overlooked or not even heard of. Thanks in advance.

um..wow. i think you need to do a lot of research. i will try my best to answer some of your questions.

1) buy your barrel chrome lined or not from the dealer. finding someone that will chrome the barrel aftermarket will be difficult much less the cost of such an undertaking.

2) as long as you have a decent barrel, barrel extension (which comes attached to your barrel), and bolt, you won't have to worry about headspacing.

3) if you want an aftermarket front sight (which is unneccessary) then you will need to install it with set screws (bad) or pay a gunsmith to install it with taper pins (good). i would just recommend you stick with the original FSB.

4) just buy a CMT upper and bolt carrier group here and pick a barrel here

you won't likely be more accurate than any quality barrel, so just pick one the right length and twist rate for you. dont worry as much about reconfiguring the placement of sights. good luck.