I am practicing the Air Rifle 3-P for the CMP national match and the American Legion match. Air rifle competitions lately have been 60 shot standing and the only time I'm in the 3 positions is with Small-bore. So, when I started training for July's 3Ps, my kneeling score was lower than usual. The next couple days of practice, I worked on my kneeling position trying to figure out what was wrong. My forearm was shaking causing the rifle to move back and forth. It wasn't until my teammate told me what she did, loosening the arm strap on the sling, when she had that problem. I had recently started going to the gym when we were in town to add some strength to my shooting. I'm not sure if that changed my positioning but when I moved my sling around, the shaking minimized and now my scores have gone back up to my average of 99-100.