I've only crossed the border 11 times, but 5,000 rounds of ammo, or the components for 5,000 rounds of ammo has been the standard I was held to:

https://www.nrcan.gc.ca/explosives/...d-transportation-transit-ammunition/9909


On a side note, pure opinion here... I have had bad luck being a military member and dealing with Canadian Border Patrol... Seems like some of them have a hard on for US Mil. I crossed 5 times as a civ with no problems, and 6 times as a mil with full anal cavity search. YMMV

Intellectual honesty is the most important character trait in human beings.