Well I finished up my load development for my new 300 ultra mag sendero and ran into some confusion. I tested 7 different powders and decided my gun loves retumbo under a 200 accubond and shoots very well. Im going by nostlers load data book and after I decided to load up with retumbo I started testing different powder charges. I was kind of in a hurry and wasent too worried about groups because I only plan on shooting up too 300 yards due to the little amount of practice time with this rifle and hunting season here in Montana is already open. Anyways, I started with 91 grains of retumbo which had no pressure signs at all and accuracy was great. Same with 93 grains no pressure signs at all and accuracy didn't change. So I decided id go with the max load in nostlers book which is 95 grains and decided id load ip 30 rounds and this would be my hunting load for the year, not even thinking about what if pressure were too high. Now, here's the confusing part... I went to the range to recheck my zero and to see what accuracy was like. First shot was 2 inches to the right and 2inches high so I made the adjustments and second shot was dead on and I checked the brass to see if there was any extractor mark which there was none at all. third shot scared me because I walked to my target and THOUGHT I completely missed the target but it took me a few minutes of confusion to realize that the bullets just went in the same hole! But when I shot the 3rd round off I got a sticky bolt and pretty good extractor mark AND the bullet completely missed the target????what the BEEP Is going on? I Took a few more shots to see what the cases looked like and where the bullets would land and it shot with great accuracy within a inch and the cases had slight extractor marks but nothing scary. Someone help me out here please?