About sixteen other things can happen, and not just with wartime P.38s, that can produce an AD during operation of a decocking lever. Many of them have happened at least once. PP-series Walthers have had their share, but so have other makes. A common source of such problems is wear (particularly from dry firing), breakage or sticking of small parts that goes unnoticed, and replacement of safety or decocker-related components by people who don't follow the proper procedures. In most Walther designs before the P99, tolerance stackups were resolved by the selective fitting of the decocking lever, which has to be timed just right. All of this merely emphasizes the importance of keeping the muzzle pointed in a safe direction when operating any control other than the trigger. It is also a good reason to restrain the hammer by hand when operating the decocking lever to ease the hammer down rather than just letting it snap forward.
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