Let's say you have an old Mauser in the closet and you've been eyeing a .223 Savage because it's deer season. Gun buybacks are the best thing that ever happened to you. Thing is, you're exactly the wrong person we want a gun buyback to target. We want that guy with the .38 special with a burned serial number who got it off a buddy that took pity on him when someone on his block stepped up and he didn't have a piece because he's done two bids for domestic violence.

That guy? He ain't coming near your buyback.

I'm not opposed to buy-backs on principle. They've been tried several times in the US, seldom without controversy. The fundamental problem, as I see it, is they're basically a stimulus program for sporting goods stores. You're effectively subsidizing the purchase of better guns, not reducing the absolute number... unless you also do something to curtail the availability of guns.

I'd also point out that it only takes one gun to kill a whole buncha people. Would Sandy Hook have been appreciably less deadly with one gun instead of three? There were only two at Virginia Tech. Meanwhile, over 1700 rounds of ammo went flying at the North Hollywood shootout and there were only two fatalities (one a suicide). Back in my hood, Ricky Abeyta killed seven people (including a 6-month-old baby) with a single handgun.

For a reduction in guns to equal a reduction in violence, you'd need statistics revealing that the availability of guns is correlated with the number of murders by guns. I haven't seen data that indicates that, although I've looked into it a few times. The correlation is muddy at best and controversial at worst.