I have a March 6.5-20 on my varmint rig and I cannot fault it. (see my most recent started thread for pics in the FS section) I was after a 6-24 but the March became available (read buyer of the scope I wanted to sell could only afford it with the March as a trade....) If a 42mm is available then I wuld suggest that as a 50mm is pretty big scope physically to carry in the bush.
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