gun part importation laws???

[unclemonkey]

can a u.s. gun dealer/smith legally have a mag (25rnd) or some other non receiver or barrel part (demil receiver chunk) drop shipped to a u.s. address from canada or switzerland?
is there a place on line where you can actually FIND the applicable laws??

 

[Sinixstar]

I imagine it all depends on the part.
I would expect that it will take some time to get through customs. Even buying something as stupid as a little piece of electronics (in the case i'm thinking of, a drum machine) can take weeks (about 8 weeks of sitting in a bonded warehouse actually) before it's released.
Don't expect any rhyme, reason, or logic in the process.
I've bought things from overseas and had 'em come straight to my house, also had 'em sit in a warehouse for weeks on end, with no update, no reason why, etc.

 

[unclemonkey]

the mags in question are swiss 24 round pe57.. they are hi cap, but for a retired/obsolete rifle..
is there a place on line where you can find the applicable laws??