I have a Colt Mark IV that has over 20,000 rounds through, between the original barrel and the Centaur Systems comp barrel I replaced it with. Back then I was reloading heavily and working up loads for IPSC. It had 4 different weight recoil springs for the various loads. Lots of fun. Still my favorite weapon. Also have a Stevens Model 34 and a Glenfield 60, both of which have had nearly 20,000 rounds through, each. Nothing else in my collection comes close to these 3; my 2 Ruger .22 autos have each probably half that. No failures of any kind with any of these 3, though if I was shooting the 2 .22s today, I would expect many ammo failures.
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I am the weapon; my gun is a tool. It's regrettable that with some people those descriptors are reversed.