For purely personal reasons that don't always make sense, I sometimes associate specific calibers as being more "appropriate" for certain types of guns. While there's absolutely no technical reason a Dakota Model 10 shouldn't be chambered in something like 6.5CM, to my tastes & preferences, a Model 10 with a classic caliber like 7x57 is a superior combination. It's the right kind of chambering for that particular rifle. I have a Ruger #1 RSI in .275 Rigby that I love. A couple of years ago I scrapped together every penny I could find and bid on a really nice case-hardened Model 10 that was beautiful. My winning plan was that everyone else with good taste would fall asleep or their internet would stop working as the auction clock wound down. Things did not go my way as the final bid was almost 2x my amount. Well at least you get to enjoy one. Congratulations on your new purchase!