I brought 200 over to Vancouver Island from Port Angeles, WA and cleared them through Canada customs also with no problems. They are duty free (made in the US) and nobody batted an eye... we almost nobody.
I met the fellow that I bought them from in the back of the parking lot at Walmart in Sequim, WA. He had a camper and I had the Cherokee. There we were loading them quickly from his vehicle storage to the back of the Jeep when up drives the Sequim Police cruiser
. He said that a concerned citizen had phoned 911 to report that someone from the US was loading ammunition cans into the back of a vehicle with a foreign plate and so he was dispatched to check us out. We had our vehicle registration checked, my passport checked, or licenses run and thankfully we were both as clean as a whistle
. We then had to explain geocaching and his first question...'are there any around Sequim, this sounds like something my kids might like!'.
Whew! After that minor delay, I had no time to go get any of the caches in Sequim before racing back to the ferry.
Otherwise, Canada had no issue letting them in. As Beanz has said... they've seen us many times at the borders - we have basically 'broken ground' for y'all to bring stuff like this in no problem.