My 2x7 Leupold had been on either a No.1 Ruger in 300 Win Mag or a No.1 in 375 H&H since 1976. I moved it to a CZ 458 and it would no longer maintain zero. Sent it back for repair and Leupold replaced it with a new scope. Have not mounted it but hope it holds up as well as the old model. (Optics are definitely clearer).
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