I'd go with the scopes that you mentioned because of their reputation. Also if you look at what the guide series weigh I think that you'll be surprised. I've been a fan of leoupolds for quite awhile but have taken quite a liking to the 2x7 Bushnell Elite with the raingaurd coating, weighs about 12 ounces. I've got one sitting on a 338 right now.

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