I think I learned something today

[Jim Flinchbaugh]

I had borrowed a 7mm mold to try a few out, Lyman mold, cast really nice!

While I had the pot hot I decided to try out a Lee 2 cavity mold, a TL design 240 grain for the 45 ACP. After goofing around wiht pot temp and mold temp I found that If I got the alloy at 600-625 degrees and the mold between 275 & 300 I got really nice fill out and shiny boolits:smile: I still was not getting a nice sharp base though. If I ran everything way hot I could get a good base fill out but frosty boolits. I dont mind the frost but the pot full of lead would get snotty a lat faster at the higher temp.
I started really leaving a big sprue on top, and that helped with the base.
My thought is to make a new sprue plate for this mold out of say 1/4 steel so it has more mass and retains heat better, then I could run the mold cooler and still keep the sprue plate hot enough to fill out the base good.
Sound like a plan? the other idea was to take a ball end mill and make a larger sprue "area" rather than 2 separate holes, maybe keeping more of the hot lead in contact with a wider, thinner area over the boolit base area.

Has anyone tried either of these things & if so, how did it work?
If not tried, do you think it might? Won't take me much to make a new sprue plate, I might even have a chunk of steel to do it with.

I notice my Lee molds dont have any "vent" lines machined in the top surface under the plate like my LBT molds do. My NOE mold is smooth on top as well, but has the heavier plate like I'm thinking of making, as well as a larger sprue hole. The Lee 45 mold has a itty bitty hole it.

The other thing I noticed is from all the molds, the shiny bullets are lighter by 1-2 grains than the frosty ones?

[454PB]

Are you using a bottom draw pot or a dipper?

I'd suggest you run the temperature up to about 700 degrees, and if the mould gets too warm, touch it to a damp cloth for a second or two every other cast.

For me, frosty is good, and a sign that the mould is at the temperature I want.

[Doc Highwall]

If the sprue plate is too tight it will not let air out and cause the bases to not fill out leaving rounded bases.

[runfiverun]

i believe rick makes a thicker plate for the 6 cav's.
you can mill a slot between the holes for more heat retention.
you can also lightly break the edge of the top corners between the cavities of the mold for better venting.

[Jim Flinchbaugh]

i believe rick makes a thicker plate for the 6 cav's.
you can mill a slot between the holes for more heat retention.
you can also lightly break the edge of the top corners between the cavities of the mold for better venting.

1&2 I intend to try
3, I had forgotten about I've done that to my other Lee molds, been playing with NOE molds too much I guess :D how come my 24 $$ mold dont work like NOE molds :bigsmyl2:

[excess650]

more heat or pressure cast

[crabo]

I've done both, and they both work. I have a RCBS 250K for the .44 and I made a larger sprue plate for it. I made it bigger and thicker. Worked like a charm. I use the countersink alot to open up holes in a lot of molds.

[Beau Cassidy]

You need to try ladle casting first. I had a similar problem with a .45 Rifle mold. After spending hours trying to cast bullets without the ladle, I broke it out and wala! Good bullets.