Obama White House: Banning Ammo Is a “Common Sense Step” We Can Take (VIDEO)

White House spokesman Josh Earnest today reporters today that banning ammo was a “common sense step we can take” to ensure “we are protecting Second Amendment rights.”
Huh?

Josh Earnest: The president has long believed that there are some common sense steps that we can take to, and what I mean is the federal government including Congress, to ensure that we are protecting the Second Amendment rights of all law-abiding Americans while also some common sense steps to prevent people who shouldn’t have guns from getting them… It’s a common sense step we can take.

How does banning ammo protect the Second Amendment?
That doesn’t even make sense.