Hey guys. I had another question and I am short on time. My Dad has found a rem. 770 in 243 for $200, He wants a bolt for my Mom and Sister to shoot. I am trying to talk him into spending some more money and buy a 223 bolt instead since he already has an AR and he wont have to add another caliber to his inventory. I realize that is a good deal on the 770 but what are the differences between 223 and 243? any help would be greatly appreciate.