REFERENCE reference 1. CEN TERFIRE RIFLES a. Must be minimum of .24 caliber (6 mm). b. Must have a minimum 16-inch barrel and be at least 26 inches long. c. If semiautomatic, they can hold a maximum of six rounds in the magazine and chamber combined. d. Must use expanding bullets that weigh minimum 70 grains for deer, pronghorn and bear, 85 grains for elk and moose, and have an impact energy (at 100 yards) of 1,000-ft. pounds as rated by manufacturer. e. It is illegal to hunt game birds, small-game mammals or furbearers with a centerfire rifle larger than .23 caliber during regular rifle deer and elk seasons west of I-25, without an unfilled deer or elk license for the season. A small-game, furbearer or unfilled big-game license is required. 2. FULLY AU TOMATIC