pitting in bullets from 9mm truncated cone? Reason?

[zsi0131]

I am a casting newbie but have been reloading for years. I started casting on friday and everything was going fine and then the bullets started to have very small pitting all over, I have fluxed the lead several times, checked the bullet mold for pitting and everything and havent noticed anything. Can anyone give me some tips on what to do?

[Lee W]

It sounds like classic oil contamination. Scrub the mold with brake cleaner and a tooth brush. At the next casting session, heat the mold for several minutes on top of the molten lead. You will get several throws of frosty boolets, but it will cool down.

[Rockchucker]

Can you post a picture of the pitting, might just be frosted boolits from a to hot mold or alloy.

[zsi0131]

I have tried to take pictures but the camera isnt the best and wont focus on the bullet. I am using a lee pro 4 20lb and have the setting on 9 as I was instructed on glocktalk as it is just range lead. I wont be running at high velocity so what do you think I should put the temperature setting at?

[ku4hx]

Mold temp and alloy temp are not the same. You need to make sure your mold is completely clean and up to casting temp. For me that means a slightly frosted boolit. A mite of Tin in the alloy will help mold fill out. I like 2%; some like less.

[Blammer]

sounds like to high a temp

[Bob Krack]

Sounds to me like deposits - ? of dirt, residue, oxides, most likely accelerated by too much heat. Sometimes scraping the pot bottom after (or even during) fluxing can stir up gunk that is safely sticking to the bottom of the pot.

Wish we could see what it looks like but since that is not the case, we can only guess by golly.

Bob

[zsi0131]

What heat setting should I be on on the lee?

[mooman76]

All the Lee pots are different. Someone might do well at 5 and others on 6 or 7 plus there are other factors like how fast you cast, type of moulds, alloy and so on. I usually cast at around 6.5 or so but I will start out a little hotter until the mould is up to proper temp. After awhile you learn to read the moulds and how your bullets are coming out and how fast your lead takes to solidify in the mould will tell you if you are too hot or not hot enough. I generally like it when it takes about 3- 5 sec. ( sounds too hot to me. I only use that hot for pure lead which takes more heat to fill out better. Try starting out at 7.5 and then lower your temp a little at a time if your mould shows signs of being too hot. If you start having trouble with fill out or it is solidifying too quick you went a little too far, turn it back up some.

[Cherokee]

Welcome to the forum ! Lee pots vary. I usually start mine at max 9 and back off as I cast, like moonman said. I always preheat my mould on a hot plate so they are up to casting temp when I start, frequently casting good bullets from the first pour in some moulds. Moulds are also different so you will have to learn what your mould(s) like. You did not tell us what mould you were using. Make sure the mould is really clean, preheat the mould and have the alloy hot when you start, you can always back off. For 40 years I cast bullets without a thermoter but now use one. You might get one yourself since the Lee settings are not temp settings.

[runfiverun]

my 10lb pot runs at 700 on 9.
my 20lb pot run at 620 at full blast when i first got it.
full will get it to 900 now, so i run it at 7.5.
how do i know the temps?
i have a thermometer.
it's how i "calibrated" my settings on my magna pots too.


if you were just casting along and the spots appeared i'd say it's gunk in the alloy.

[DLCTEX]

My 10# pot is at 700* when set on 6.5, but each unit will have it's own range.

[mooman76]

I've even heard of some running their pots at like 3-4 and I don't think mine will even liquify at that setting.

[bruce381]

sounds like dirt that gives a pitty look to the boolit.

[Bob Krack]

sounds like dirt that gives a pitty look to the boolit.

Exactly, and sometimes it is worse when the distance from the spout to the sprue plate is excessive (as in over 1/4" to 1/2").

Bob

[popper]

Assume it is dirt and mould too hot, fix for both. Clean the mould real good for next session, lube pivots. It started ok, I assume good fill out, no wrinkles or swirls. Then it looked real cratered. Slow down the casting pace, let the mould cool a little to see if the pits go away. Maybe turn down the pot, just hot enough to flow good (per Gear). Get a thermometer or PID and keep the pot 1/2 full, the temp goes up as the pot moved to empty.

[MaineJim]

FWIW my Lee 20 pounder runs at 790 degrees when set at 5.5 on the dial.