I actually missed this story when Guns and Ammo magazine fired Dick Metcalf back in November for a column suggesting that increase gun regulation doesn't infringe on 2nd Amendment rights. The quality makes it very difficult to read, but the Times piece links to a PDF of Metcalf's column. First: Guns and Ammo has every right to fire Metcalf, just as A&E had every right to suspend (fire) and ultimately rehire Phil Robertson. That point is not debatable. What is debatable is whether a magazine for gun enthusiasts did the right thing in firing Metcalf for his words.
As Jazz Shaw wrote at Hot Air at the time Metcalf was fired, it's not hard to see why G&A made the move. Among other things, Metcalf invokes the lamest of anti-gun arguments; he compares licensing people to drive with the right to keep and bear arms. Yes, he goes on to distinguish between the two, that one is a constitutional right and one is not. But he then dismisses that difference with his argument that guns should be treated as cars.
G&A readers were outraged; the magazine now concedes it never should have published the piece. That's where I think this gets interesting; should Metcalf be fired for a piece the magazine decided to run, or should the person who decided to run the piece get fired?