I have another question about assembly vs manufacturing.  if I buy an assembled AR15 that has all the parts on it except the butt stock, hand guards, grip and sights, am I manufacturing if I add those parts and sell it? what if i sell it in that configuration (no grip, hand guards, butt stock and then sell the parts (and the labor to put them on) separately?

dont yell at me, just asking.

From what i understand, your GTG as long as you arent taking a rifle and converting it to a pistol or vise versa, also building a title one firearm and converting it to a NFA weapon would obviously be manufacturing, everything else seems like assembly to me, but i am not an expert.

If you buy firearms, add or do stuff to them and resell the firearms, that's manufacturing.  

If you sell parts to customers and install them to the customer's gun for them for a fee, that's just gunsmithing.

ATF Ruling 2009-2

Any person who installs “drop in” replacement parts in or on existing, fully
assembled firearms does not manufacture a firearm, and does not need to be licensed as a
manufacturer under the Gun Control Act. A “drop in” replacement part is one that can be
installed in or on an existing, fully assembled firearm without drilling, cutting, or
machining. A replacement part, whether factory original or otherwise, has the same
design, function, substantially the same dimensions, and does not otherwise affect the
manner in which the weapon expels a projectile by the action of an explosive. Any person
who is licensed as a dealer, which includes a gunsmith, and who installs “drop in”
replacement parts in or on existing, fully assembled firearms as described in this ruling
does not need to be licensed as a manufacturer under the Gun Control Act. Any person
who is engaged in the business of installing “drop in” replacement parts in or on existing,
fully assembled firearms as described in this ruling must be licensed as a dealer, which
includes a gunsmith, under the Gun Control Act.

Ruling 2010-10 lays it out pretty nicely:



https://www.atf.gov/regulations-rulings/rulings/atf-rulings/atf-ruling-2010-10.htm
Rulings are located here:


https://www.atf.gov/content/library/rulings





 

Unless I read it wrong (which very well may have), it would look like a 01 could take a firearm in their inventory , cerakote it and sell it right? This being since it only cosmeticly modifies the firearm.

here comes the gray!

Not a damn bit of gray.
Did you read those ruling posted above?

Coating, painting, and engraving are not considered manufacturing processes.  Parkerizing, bluing, and anodizing are.

So to revive this thread. How would 2015-1 hinder taking an item from your own inventory cerakoting it then selling it. (This being a new item that has never been out on a 4473).