I've always kept my old scope boxes, and now use the boxes (even though I no longer have the scope that came in it) to encase a newspaper or bubble wrapped scope OFF the rifle - with the rifle broken down, also.
Look at it this way - whomever gets the rifle is going to have to rezero it anyway, so why not ensure it arrives intact ?
In mailing or shipping (I use USPS Insured Registered Priority Mail only), it's imperative that the shipping carton/case/whatever have ample crushable packing in & around the separate pieces, so that they are both protected from outside blows and from banging around inside, hitting each other.
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