I have a 4013 that I bought new in 1995. It has only been shot around 500 to 700 rounds using standard .40 S&W, no hot stuff. It has the dual recoil spring setup. It shows no such wear like that. In fact, it has only very slight wear. By the way, springs are cheap in the long run, so I replace them more often then I probably need to. FWIW

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1st Signal Brigade, RVN '70