They have been doping the 223 for years and the charts should be right on..tell you get to a range to check how well your gun shoots at longer ranges.Setting you guns at 1 ot 1.5 inchs high at 100 yds. should put you 3 or 4 inchs low at 300 yards and well inside min. of doggy. Write down the ballistics calculation to 500 yards ever 50 yards and TAPE it to your gun stock so all you have to do is look a the stock to see what your drop is for that long shot. The reason I love the AR's is because you can change upper if you want a lighter gun.