Got my bcm 16 bfh upper in the mail. I understand you need to wipe down the factory oil and apply clp of your choice on the internal parts. Does that mean external parts as well and on the barrel itself? Sorry this is my first AR. Also does anyone clean it as well after wiping the factory oil? Just in case there's some unwanted debris

There's actually a really helpful sticky on the top of the thread topics on the previous screen. Helped me immensely when I got my first AR. I wouldn't worry about the outside of the barrel too much unless it actually starts rusting. Somebody much more experienced will probably chime in too but that's a good place to start.

Maybe you should post your question in multiple forums...

(sarcasm, for those of you that aren't catching on)

Always assume good intent.

Dude..... First cleaning is just what it sounds like.  Anything thick, sticky or not slippery gets cleaned and lubed up.  Storage oils are thick. Use anything including Brake Clean to get it off.

 From there, lube as instructed and have fun.

Posted in the wrong section so I posted on here. Thanks anyway

Give any new firearm a thorough cleaning and lube.

Not only is it needed but it will familiarize to an extent with your new gun.

I find it enjoyable, you may as well.

As others said, clean off the preservative.  Clean the barrel to make sure there is no debris/grease in it before shooting.
Barrel and chamber are chrome lined, so essentially "rust proof".  No need to lube/oil inside barrel. Some say (a lot of) oil in barrel can cause hydraulic pressure when shot (I don't think it does).  Light coat wont' hurt anything (but again, not needed).
Exterior of barrel is Parkerized.  From BCM "...phosphate finished to create a porous surface to absorb oil as to resist against corrosion from the elements."  My understanding (as evidence by BCM) is that you would wipe that down with an oily rag/patch to get some oil soaked into the finish to protect the exterior.  I think even if you don't the Parkerizing makes the exterior of barrel essentially rust proof.

For rest of rifle, check out sticky top of this forum AR lube points