I've brought heaps of longneck bottles back from overseas and not had any problems. Just wrap em in my holeproof explorer socks for protection.
Don't know how cans would go through? Anybody tried with cans?
I've got and old ozito drill and just hold it at a slower speed with a g clamp. Takes about half an hour to crush 4kg grain so I just leave it doing its thing with no problems.
Bribe, I bought my mill second hand with the extra hole already drilled. I've got a herms system and find the crush...