I'm trying to load up some .223 using 75 gr. A-Max polymer tipped bullets. According to the Hodgdon load data, my C.O.L. should be 2.25", but with the seating die cranked down as far as it will go, I'm still significantly too long. Any suggestions? As it is now, the first round I loaded is 2.303 and is too long to fit in an AR magazine. Am I just out of luck trying to use these in an AR? Are they only supposed to be used in bolt guns?