I am just starting to reload .223 and started with a Dillon 650XL and the RT1500 case trimmer. I set up the case prep toolhead with the Dillon sizing/decapping die and the case trimmer. After setting up the trimmer for 1.75", and I ran some brass through the process. I measured the first few cases and the case length was fairly consistent at 1.748"-1.751". After running several hundred case through the process, I decided to measure the case. The case length varied significantly; ~1.738-1.750". The trimmer dies is fairly tight and so is the locking nut for the trimmer. I find it difficult to tighten the trimmer too much because when you tighten the trimmer, the trimmer dies get loosened. So, my questions,
1. Will these shorter cases (1.738" or so) be alright to load? Or, should I scrap the short case? How short is acceptable? I am shooting an AR rifle.
2. Is this variation normal for the trimmer? Or, is there something that is not right with the setup?
Thanks again for your help!