Some variation of the words "for sporting purposes" can be found repeated over and over again in the interminable list of "gun control" laws burdening the American people. Given the history of those words, used that way, JPFO readers have plenty of reason to want to see them excised from American legal code, like the cancerous tumors they are.
But it's more than "merely" the fact that the "sporting purposes" requirement for firearms and ammunition appears to have been lifted directly from the gun laws of Nazi Germany, but the fact of why a government would want to limit the people's access to firearms to those that are better for recreation than for the deadly serious business of defending one's family, liberty, and life. There can be only one reason for that: the government does not wish the people to possess the means to effectively defend those things.
Go. Read the whole thing.