From the pictures, what you have doesn't look like bullets to me, although they could be cut up bullets used for something else. Are the marks on them caused by the tumbler? If not, do you think those marks resemble tooth marks. Could be a pain bullet or other lead item where some poor guy had an arm or leg sawed off and was biting on it. Also, I have a round lead bullet that looks like an Indian pounded on it with a rock to make it smaller so it would fit in his gun. I say that only because of the context in which I found it, among other Indian artifacts. Other than that, fishing weights? Actually it's a rather tough call.
Interesting find but in the future, I wouldn't tumble anything made of lead. If it's an artifact, it can be ruined doing that.....not to mention the hazardous pollution that could be produced. I'd clean out the tumbler real well and use gloves to do it.
Could be part of a lead bar that would be used to cut chunks off of to be melted and poured into a ball mold. Lead finds in a field are positive. I would grid and dig every signal.
I'm thinking something Native American or CW. We have a family farm and when great grandparents lived on it tons of arrow heads and broken pottery and pipe heads. But they were farmers so didn't think anything of it and threw it in the creek. Over the hill is a huge mound that's in a creek bottom. It has layers and been there for over 150 years since the farm the lands on was built 1830. Ours was built in 1853 and farmed till 1992. Anyways Indians were all through out WV in great numbers, they were pushed out during the Indian wars and the rest in the CW. Can't wait to hit the old farm for coins we had a stage coach road the the main road 30 feet from our front porch. And my gg grandpa was a cacher.