I just received my new Caldwell chronograph and had some interesting results. I was working up a max load for my 16” AR with 250gr bullets. I was loading with Lil Gun (older can), measured each charge, and zeroed the scale between each load. I’m surprised on the large range of speeds I received.
40gr. 41gr. 42gr.
2345. 2289. 2372
2264. 2339. 2372
2424. 2327. 2342
My highest velocity came with the lightest load. Is this common? Am I doing something wrong? Does it make a difference because it’s an AR. I have been loading a long time and I thought that one grain of powder makes a big difference. The chrono was about 15’ away from muzzle because when it was closer, I was getting goofy reading because of the muzzle break