Ha! Bet that got your attention. It's a fact that you don't cast as well as you think. I thought I was good until my partner go to messing with impact coating moly as a hard lube. I mean, he was meticulous in casting. Fluxed, let melt set for 20 minutes to settle, then cast and didn't return sprues or culls to pot. Then culled for defects. He was casting a special nose pour bullet for the .32-40.
The process called for tumbling the bullets in jeweller's media with liquid moly added for 20 minutes. Then remove, rinse and let dry. We expected perfect bullets. The first batch of 100 we did, we culled over 70 for internal flaws. As casters, we're use to seeing base flaws at the sprue. We had plenty of them, we also had flaws on the side of the round nose, on the driving band and the bands between the lube grooves. Plenty of flaws on the dide of the base. Flaws on 70% of the bullets we did. We ran many batches in order to get enough to test. In the end we gave up the project because even though they gave good accuracy without lube which was the objective, the moly tended to coat the barrel and was a bear to remove. In order to get the accuracy, We hand lapped several barrels and that was a several day project in itself.
The flaws evidently occur in almost all cast bullets under the skin. The jewellers media is a hodge podge of metal shapes used to polish jewelry. The steel media is evidently enough to impact the surface of the bullet and cause imperfections under the skin of the bullet to sink in and expose the void.
All I know is that I thought I made good bullets and it deflated my ego.
Best solution is make 'em as good as you can and shoot 'em. That's all you can do.
Like sausage, it's good but don't ask what goes into it. You might be surprised./beagle
The process called for tumbling the bullets in jeweller's media with liquid moly added for 20 minutes. Then remove, rinse and let dry. We expected perfect bullets. The first batch of 100 we did, we culled over 70 for internal flaws. As casters, we're use to seeing base flaws at the sprue. We had plenty of them, we also had flaws on the side of the round nose, on the driving band and the bands between the lube grooves. Plenty of flaws on the dide of the base. Flaws on 70% of the bullets we did. We ran many batches in order to get enough to test. In the end we gave up the project because even though they gave good accuracy without lube which was the objective, the moly tended to coat the barrel and was a bear to remove. In order to get the accuracy, We hand lapped several barrels and that was a several day project in itself.
The flaws evidently occur in almost all cast bullets under the skin. The jewellers media is a hodge podge of metal shapes used to polish jewelry. The steel media is evidently enough to impact the surface of the bullet and cause imperfections under the skin of the bullet to sink in and expose the void.
All I know is that I thought I made good bullets and it deflated my ego.
Best solution is make 'em as good as you can and shoot 'em. That's all you can do.
Like sausage, it's good but don't ask what goes into it. You might be surprised./beagle