First, since you are brand-new at Treasurenet (three posts so far)... welcome to the What-Is-It? forum, the best place on the internet to for getting CORRECT identification of a mystery-object.
About your unidentified metal ball:
As my posting name indicates, pre-1900s projectiles are my specialty area. Your photo showing it next to a US 25-cent coin indicates its diameter is approximately 1.25 to 1.5-inches. That absolutely excludes it from being a musketball. You say it is non-magnetic, so it isn't made of iron/steel. At this point, we need to know whether it is made of a pink-ish metal (copper) or a yellow/orange/golden metal (like brass) or a silvery metal (like lead). If you don't already know its metal-type, please make a teeny-tiny scrape on it and tell us whether it is a pink or yellow metal or silvery.
If it is a silvery metal, we will need you to use a Digital Caliper to measure its diameter in 1/100ths-of-an-inch.
We also need to know the general location where you found it (state and nearest town)... because if there was never any Military activity there, it is extremely unlikely to be a Military-usage ball.
