But for that you need all the parts, including the gunpowder. And for the gunpowder you need a special permission for handling explosives, at least in my country. So you just move into areas of even more difficult to procure things. it seems far easier to just buy a gun and ammunition somewhere else and take it over the border into California.
If 50 pounds or less of commercially manufactured black powder is being purchased, and the powder is intended to be used solely for sporting, recreational, or cultural purposes in antique firearms as defined in 18 U.S.C. 921(a)(16) or in antique devices exempt from the term “destructive device” in 18 U.S.C. 921(a)(4), no form is required. However, if the black powder is being purchased for any other purpose (regardless of quantity), the purchaser or other transferee must possess a federal explosives license or permit.
But for that you need all the parts, including the gunpowder. And for the gunpowder you need a special permission for handling explosives, at least in my country. So you just move into areas of even more difficult to procure things. it seems far easier to just buy a gun and ammunition somewhere else and take it over the border into California.
In America you MIGHT need to show ID for age verification purposes in most states when purchasing gunpowder.
There is no country wide law requiring a permit to purchase everything you need to make bullets.
The exception might be buying a large amount(like 50lbs) but low pounds(<10lbs) is legal without a permit.
If 50 pounds or less of commercially manufactured black powder is being purchased, and the powder is intended to be used solely for sporting, recreational, or cultural purposes in antique firearms as defined in 18 U.S.C. 921(a)(16) or in antique devices exempt from the term “destructive device” in 18 U.S.C. 921(a)(4), no form is required. However, if the black powder is being purchased for any other purpose (regardless of quantity), the purchaser or other transferee must possess a federal explosives license or permit.
[18 U.S.C. 845(a)(5); 18 U.S.C. 926©; 27 CFR 555.141(b), 555.26(a)]