Not at all if you have the clearance and paperwork ready. Funny thing, gunpowder manufactured in Canada is shipped to USA, put into consumer sized packaging then shipped back. The product code at the border will indicate USA manufactured goods, no tariff, but must display product information in both Francais and Anglais if for retail distribution..
Rim fire ammunition is abundant. I see the new .17 WSM ammo, but yet to see a rifle in that caliber. Not that I would buy one anyway. I could reload .204 Ruger cheaper than the price of .17 RF Win-Mag ammunition.
Ever since Enemy at the Gate, the Mosin's became the rifle every gun nut just had to have. Useless for hunting with fmj ammo. Guys pull the bullets without spilling a drop and press in 150 gr sgk's. The 7.5 mm Swiss item might show up at a gun show where 450 pound fat guys arrive in their camo to trade suspect hunting tales, and brag of running shots with 50mph cross winds at 600 yards. Or was it a thousand?