It always wise to get unidentified objects checked here in the What-Is-It? forum. Sorry, but in this case, almost all of the bullets in the photo are modern era "Semi-Wadcutter" bullets, made specifically for target shooting. The only object in the photo that even might be a civil war era bullet is the largest one, second from the right in the photo. But in that photo it looks too smashed for us to identify it with certainty. Please post a couple more photos to show us its other side.