Lee 375-250 cast bullet base

[rp85]

good afternoon;

two cavity Lee 375-250 cast bullet mold issue. makes no difference both cavities are having same issue. a bullet will have a hole in the very center of bullet, almost like someone drilled a hole into the very center of bullet. cast temp 710-ish, alloy is mostly wheel weights. tried all ways i could think of but nothing seems to work. operator error of some sort. thankful for any input.

rp

[BK7saum]

The hole is due to the drawing of lead into the bullet as it cools/solidifies in the mold. The problem is the sprue puddle is not large enough amd/or the sprue plate is too cool.

[BK7saum]

Because the sprue cools too soon, it creates a void as there is NO molten lead to pull into the bullet.

[Mk42gunner]

I agree with BK7saum: pour a bigger sprue puddle.

Robert

[Dusty Bannister]

It would not hurt to cast fast and may also need to increase the temp of the melt. Do not stop to examine things, just cast and keep casting.

[GooseGestapo]

Also, need to pre-heat the mold some more.

[RobS]

May need to increase lead temp about 25 to 30 degrees and/or create a large sprue puddle on top of the sprue plate to get it hot enough to keep the lead flowing into the cavity prior to solidifying.

[T-Bird]

I'm a dinosaur I guess, I use a side pour ladle and let the weight of the metal in the ladle aid the filling of the mold. Due to the nature of ladle casting, pouring adequate sprue isn't an issue. I never have seen a hole in a boolit.

[gwpercle]

To prevent the "hole" you need a sprue puddle for the hardening boolit to draw from ... And ...
Most Impottantly ... the puddle must remain liquid long enough for the hardening bullet to draw from ... I get my mould and melt hot enough for the sprue puddle to stay liquid 3 to 6 seconds ...
If you don't do this you aren't doing nothing .
Side spout ladle pour (me too) or bottom pour ...the sprue puddle has to stay liquid while the boolit cools and draws metal .
Gary