I have a new Model 12 FTR and I am getting horrible results from it. I initially took some old ammunition that was hand loaded for my grandfather in 1991 to the range and it shot anywhere between 0.75 to 2 inch groups with it. I then took that brass (which was quite old and mixed) and full-length resized it while I waited for my new Nosler brass to come in. I full-length resized and trimmed each case. I am using A-max 155 gr bullets with Win-748 powder. I loaded rounds in 0.5 gr increments from 40 to 43 grains. When I went to the range the next time to try these new rounds out I had groups between 1.15" and 5.5". Most groups were above 2" and most were horizontally dispersed. The 5.5" group was almost entirely horizontally dispersed.

Some additional information is that my scope is a Falcon 5x25-50. I also did not clean the gun between the first 30 shots I put through it and the last test batch that had the bad results. I will be getting another person with more shooting experience then me to see if they can get better results. Any help would be greatly appreciated!!