it is ten correct?
It's either 10 U.S. parts or no more than 10 imported parts. I can't remeber which. What a really dumb law.
ETA: You can't use 10 or more of the imported parts on the list.
27 CFR section 178.39
(a) No person shall assemble a semiautomatic rifle, or any
shotgun, using more than 10 of the imported parts listed in
paragraph (c) of this section if the assembled firearm is
prohibited from importation under section 925(d)(3) as not
being particularly suitable for or readily adaptable to