I brought some brass, powder, and loaded ammo across last fall... WON'T do it again.
Our CBSA guys were good about it, albeit with a little stink eye, and a very stern warning about getting caught.
They told me to get the proper paperwork done if I want to be safe.
Haven't tried the paperwork yet. Just as easy to contact Lois at THE BULLET BARN.
Service was AWESOME.
Not worth getting your ass kicked out of the U.S., and all the legal crap that will bog you down.
Just my 2 cents.
Later...