The link below to Randy Wakeman's site doesn't claim 1/2 million rounds through one gun, but 100-million rounds over 18-years through some 150 rentals is dang impressive:

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The Benelli Montefeltro / M2 line is the most durable autoloader in times past, and is the gun that Zeke Hayes would buy tomorrow for himself. The Beretta 390 is in the same league, with a bit more cleaning required as you'd expect of any gas gun and perhaps the occasional broken or cracked action rod to replace.


Randy Wakeman Outdoors


Forgive me my nonsense, as I also forgive the nonsense of those that think they talk sense.
Robert Frost