An interesting engineering reminder
From Tam (Our Lady of Snark) comes this reminder - It is entirely possible for an "autopistol built before the Panama Canal" to be in perfect working order with only normal maintenance being applied. It may not look factory-new, but it will continue to work properly for almost a century..
And while you have to be a tad careful about the ammo you feed them, you can find functional examples of firearms manufactured in the Civil-War era.