Until 2 months ago, a Nylon 66 was the only gun I'd ever sold. Bought it used for about $75 and it had been fairly beat. The spring blade type of rear sight has a screw that can get stripped (internally, not the screw itself most of the time). If that happens you'll never make another accurate shot unless you get it smithed. Back when I had mine and decided to sell it, I didn't know Bert or any other smiths so I sold it.