Fin On My Boolit?

[barrybrice]

When I cast a bullet I am usually left with a little fin or seam of extra lead around the bullet. How do I stop this from happening? My mold is the RCBS MOULD 40-180-FN 2-CAVITY (.401).

[*Paladin*]

Are you lubing the alignment pins before casting? I've noticed just about every time I forget to lube, the two halves don't mate/close all the way and I get fins.

[Ickisrulz]

Too much pressure when pouring?

[Alchemist]

Check for tiny lead splatters on the block faces....that or a small burr can keep the mould from closing all the way.

Hope that helps.

[John Boy]

Any or all of the following because the mold halves are not completely mated:
* Hold the closed mold, tightly closed, up to a light. If you see day light in the mold at the nose - the mold is possibly Ka Putz (warped) or you need to continue below
* Clean the mold with Brake Cleaner - scrub with toothbrush - spray again
* Check and remove any lead spots on the inside of the mold halves
* Lube the pins if they are not
* Squeeze the mold handles tighter
* Hold the mold handles and try to wiggle them. If they do, tighten the handle bolt

[Boolseye]

Yeah, sounds like something's keeping the mould faces from joining perfectly, a little spatter of lead or some such. I had a few little fins on some rifle boolits the other night, too. They cleared up. Mated, that's the word (thanks John Boy!)

[EMC45]

A tighter squeeze. Or it could also be that you are pressure pouring and it is being forced out of the vent lines. In my casting (Lee bottom drip pot) I usually hold about an inch away from the nozzle and the fins go away. Otherwise if I put the sprue hole up to the nozzle I get bad fins.

[dragonrider]

Check for burrs or raised area around the locating pins and thier mating holes.

[songdog53]

I agree with the folks above and i found when i find a fin on a bullet is usually some lead on mold block that keeps it from closing completely.

[Tatume]

Any or all of the following because the mold halves are not completely mated:
* Hold the closed mold, tightly closed, up to a light. If you see day light in the mold at the nose - the mold is possibly Ka Putz (warped) or you need to continue below
* Clean the mold with Brake Cleaner - scrub with toothbrush - spray again
* Check and remove any lead spots on the inside of the mold halves
* Lube the pins if they are not
* Squeeze the mold handles tighter
* Hold the mold handles and try to wiggle them. If they do, tighten the handle bolt

Also, when you close the mold halves, rap the back of the handle with your sprue mallet while you are squeezing them closed. Hit it right where the pin secures the block to the handle.