On my 6BR I'm at 500 rounds now and I've had to reduce the charge several times. After initial load development I was shooting 29.8 in a good node. After stepping down .2 and .2 again (because of hard bolt lift) I shot 29.4 this morning and got hard bolt lift and swiping. My accuracy is still great. Initial load was developed at 50 deg and today way 60. 107SMK Varget BR4. I don't have a chono.