Well he wasn't kind enough to specify a round capacity for weapons greater than zero. A few follow-up questions are in order. Essentially he hasn't articulated his position (although he has already implied that he thinks all gun ownership is bad anyway) well enough for you to debate him. Such as, what is the ideal limit on magazine capacity? Why? Should people be allowed to own easily concealable semi-automatic handguns, regardless of capacity? Why or why not? If magazine capacities are limited to x, and you do not have time to fumble around, is it OK to carry y guns, thus giving you x*y rounds loaded into guns? Why or why not? Is a device useful for killing humans good or bad to have? Why or why not? Is it wrong to own a device designed solely for killing humans? Why or why not? Is it always bad to kill a human being, or are there situations where it isn't? Why or why not?