The centerfeed actions have the most going for them but I like 'em both. Had some smooth flat backs(staggerfeed) ever the years. there is a rather significant difference in the magazine and the inlet between the two. I would look for an unmolested rifle too. Twisted actions from improper barrel removal techniques is possible. If it is tweaked you can usually pull the bolt out and look down the raceway and tell. Also if it is just an action make sure there are no stripped holes.
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