I'm fairly new to reloading. I have 300 win mag that I am reloading for. I worked up loads with IMR 7828, hornady spent casing and Hornady Interlock 180 gr BTSP. I went in increments of 100 fps starting at 64.2gr-2500fps, 67gr-2600fps, 69.7gr-2700fps, 72.4gr-2800fps, 75.2gr-2900fps. I didn't really know what to look for when figuring out what was too hot, so i just went up and saw which fps grouped the best. There wasn't any obvious damage to the casing. I ended up going with 74.9gr, which is supposed to be 2850fps. I realized I am supposed to be looking for indentions on the back of the bullet. I noticed that all the bullets at 74.9gr have a slight full moon mark. Does that mean the load is too hot? Have I done damage to my gun? I can't get it to group very well.