Since I have started reloading, I have only reloaded 1 type of bullet (Nosler CT Ballistic Silver tip). I am going to try a different type (Nosler AccuBond). I have found that the 2 different bullets have different seating depths (COAL measured @ OGIVE, CT Ballistic tip = 3.275, AccuBond = 3.318). To determine my seating depth I am using a fire formed case with a slightly crimped neck with a sharpie colored bullet, chambering it 3 times recording the measurements then after determining the avg. subtracting .015. Is it common that 2 different types of bullets would have such variance in COAL? It seems odd to me.