for varmints , i have a .22 hornet , and a .22-250 , and i would recommend the .223 for you from those choices you asked about , the ammunition is cheaper , and it' s still very accurate out to 300 yards , which is about as far as the normal person should be shooting. the 2 inches extra of barrel will increase your feet per second or ( fps ) for short , but the biggest thing about accuracy that i know of is barrel weight and design. for stiffness and rigidness , the barrel would also be even better if it had been fluted too help in cooling the barrel down. the action is also important for accuracy , and the bolt to barrel lock up