:Off-centre holes inside the 'Odd" ball is the only thing I can think of. This is quite possible and there is the Odd ball I cast that has an interior hole with a perfect exterior.
: Foir example, I just cast up a bunch of .662's from an old (new)Ohaus mould that hadn't cast more than about 50 balls prior to me getting it. After a couple to perfect the heat of the pre-heated mould, they came out perfect - every one of them. I should say here that I run my temp a bit higher than some do, but I like all of the balls to be perfect and with the pot's thermostat on max all the time, That's the way the bottom pour works best for me casting balls with pure lead.
: I weighed them on the electronic scale, and 1 out of the 30 good casts, was 8gr. under all of the rest. The majority of them were within 1 gr. on the scale. The one that was 8gr. light, was sliced open and had a tear-prop shaped cavity just under the sprue.
: Due to not having the stability of rifling, any defect like that could immediately affect the ball, I'm, sure, much more dramatically than the same defected ball in a same calibre rifle, at close range. (supposition)
: At one time, I tried casting 1/2 balls(.684 balls -14bore rifle) for the string cut. It worked, but they didn't hit the same place as solid ball (close), being much lighter. In damp weather, it is very difficult, almost impossible, to cut a string with a large slow moving ball of around 1,000fps or less.The string just stetches and flaps out of the way. I could hit em almost every time, but not cut them. The 1/2 balls (kinda cheating - but not)solved the problem which showed the rifle, due to rifling, stabilized and shot quite accurately at close range, the grossly mutilated balls. Some had shrunken surface cavities, and the weight range, while close, probably varied cose to 100gr. In loading, the 'flat' of the surface wasn't always perfectly flat at 90 degrees to the bore. The point is the Rifle will shoot fairly well, a ball with gross defects. The smoothie is much less forgiving I feel.
: Perhaps we cast in a similar manner, Squire John? 1 out of 30 being bad, isn't, too bad!
Daryl