Quote from James Wesley Rawles' Survivalblog.com, from March 12, 2007:
"I should also mention that with a new Federal magazine ban (H.R. 1022) pending, make sure that you line up a large supply of magazines to buy before--or coincident with--your next purchase of any high capacity rifle, pistol, or submachinegun. Budget for buying at least 8 and preferably a dozen or more spare magazines for each gun, and don't delay in doing so! If you dawdle, you may end up kicking yourself. (High capacity magazine prices are likely to at least triple if the ban passes!) I'm often asked why I'm "such a fanatic" about buying so many spare magazines. Here it is in essence: Most modern guns--especially those made of stainless steel--will last two hundred or three hundred years, with typical civilian use. It is not inconceivable that some of your great-great-great-great grandchildren will inherit functional guns from your collection in the year 2300. They may still be in commission then. But unless you buy a lot of spare magazines, odds are that they will be inheriting guns with no magazines. Let's face it. the magazine is the most fragile part of a modern firearm. Magazines get lost--especially in combat. Magazines get stepped on or otherwise dented. Magazines get broken. Magazines might also become a political target and get confiscated. So if you want a 300 year supply of magazines to match the potential 300 year useful life of a semi-auto rifle or pistol, then we are talking about a lot of magazines. Stock up!"