Gunboards Forums banner

problem getting a clean cast bullet

3K views 12 replies 9 participants last post by  triggermonkey 
#1 ·
Hi all,
I am new to casting and am having a problem getting a bullet to come out of the mold clean.
I am using a lee bullet mold (aluminum blocks) and a lee melting pot.
For flux, I am using wax and I make sure the blocks are preheated.
I have used several types of lead (reused air pistol pellets, lead weights from who knows what, reclaimed bullets and I've mixed 5% tin with some of the pellets) and every time, I still come out with bullets that do not fill the mold completely (I get the swirl or layered effect).
I've tried experimenting with different solutions, but always (several hundred casts) the same result. :confused:

Any help from the veteran casters out there? Show me the light bulb!
 
#2 ·
Try sooting the inside of the mold. Hold one of the mold halves over a flame from a match to coat the inner part of the mold with soot. Then do the other half. Preheat your mold and pour in your lead.
 
#3 · (Edited)
Do you have a casting thermometer to see if the furnance temperature is correct? The lead may have to be hotter.
Midway sells a release spray that helps the bullets drop out after casting.
 
#4 ·
When I've had that problem it's always been that the lead wasn't hot enough, or the mold hadn't heated up yet. The mold usually is OK after 5-10 castings, and I just throw them back in the pot until I'm getting good bullets.

I've heard that newer wheel weights containing zinc may cause this problem. I just got a bucket of them recently, but I haven't melted any down in 15 years, so I haven't experienced this.
 
#9 · (Edited)
I agree. Zinc contamination would be a different problem in my experience. Just getting a swirl or layered effect is usually a sure sign that either the mold or alloy is not hot enough. Or both. Crank up the pot a little more and as was stated if the bullets don't look right when droping, drop them back in the pot until your mold heats up enough.
You also need to smoke the cavity of the molds as was stated but not smoking would only cause them to be hard to drop or have dimples or other such deformities. Not the swirls or layered signs you are talking about.
I always clean any new Lee mold with isopropyl alcohol and then clean the cavity with a toothbrush and toothpaste. Have even used rubbing compound to smooth it out a little. Used sparingly and very lightly with a Q-tip as rubbing compound is a bit abrasive. Clean again with the alcohol and let dry. Then smoke the cavity with a wooden match. Follow the directions for lubing the mold before casting.
Your problem seems to be your temps though.
If you want to cast and handload, I suggest you get the Lyman Cast Bullet Handbook and the Lee Modern Reloading Second Edition. Great info in both for casting.
 
#7 ·
Scrub your mold out well. I usually degrease with brake cleaner outside, then scrub with purple power or another aggressive detergent inside, rinse, and let dry.

Then make sure your lead is hot enough. For virgin alloys I can run them a bit cooler, but with range scrap or wheelweights I have to run my lee pot on 8 or higher to get total fill out. You might get some frosting of the bullet; this doesn't hurt at all.

The drop out spray referenced is ok but if you have a real sticky mold it will just add layers to the mold and not solve the problem. You might want to try 'lee-menting' the mold as folks on the cast boolit forum call it; simple enough. Just get the mold hot, fill it, cut the sprue off, but leave the bullet in the cavity. Next drill into the base of the bullet, and put a small screw in it. Now drop the bullet out. Coat with a paste made from cleanser (I use comet) and water, put back in the mold, and chuck the screw into a drill. Spin about 50 turns in each direction. Now clean your mold. Guaranteed it will drop perfectly every time after this as all the little burrs and imperfections have been polished out, but not enough to really open the mold any.
 
#8 ·
Bingo nailed it. Try this stuff if you are going to try to get Lee molds to work.

I've got 5 Lee molds, and 3 of them the sprue plate does not lay flat on top of the mold. This causes flashing at the base of the bullet. Lee molds are inexpensive, but also very cheap (think - "you get what you pay for") and not worth the hassle to make work if you ask me.

Also the only way I could get decent mold fill is to cast them frosty no matter what alloy I was using, but that isn't that big of a deal...
 
#10 ·
Bingo nailed it. Try this stuff if you are going to try to get Lee molds to work.

I've got 5 Lee molds, and 3 of them the sprue plate does not lay flat on top of the mold. This causes flashing at the base of the bullet. Lee molds are inexpensive, but also very cheap (think - "you get what you pay for") and not worth the hassle to make work if you ask me.

Also the only way I could get decent mold fill is to cast them frosty no matter what alloy I was using, but that isn't that big of a deal...
Not cheap but inexpensive. They most often times than not need a little tuning. Check the hole in your sprue plate. I also have five Lee molds, two single cavity and three double cavity. Most all had some burrs left in the hole of the sprue plate. I don't know if they drill them or punch them but sometimes they are left with burrs and the hole is not completely round and the burrs will cause a scrape spot on top of the mold and may not lay flat. A small pocket knife can remove this. If that doesn't help you may have a bent sprue plate. Flashing at the base of the bullet is not good. You want a good flat, square base. Especially with any gas checked bullets.
Frosted bullets don't hurt accuracy.
 
#11 ·
Success!!

Thanks fellas!!
Great advice! They look great.
I tried a number of the suggestions, specifically cleaning (break-cleaner and rubbing alchohol) the mold and moving the heat up on the pot. I had been running on 8 but moved it to 9+. There really isn't a 10.
I can now shoot the crap out of my 45 LC Ruger for a mere pittance,
the wife will be thrilled :D
 
#12 ·
Thanks fellas!!
Great advice! They look great.
I tried a number of the suggestions, specifically cleaning (break-cleaner and rubbing alchohol) the mold and moving the heat up on the pot. I had been running on 8 but moved it to 9+. There really isn't a 10.
I can now shoot the crap out of my 45 LC Ruger for a mere pittance,
the wife will be thrilled :D
All in all not bad looking boolits. Did you smoke the molds? There are a few little rough spots, maybe a little dross in the alloy or your mold may still have been a little cool, but should shoot fine. Do you use a bottom pour pot or do you laddle cast?
 
#13 ·
Yeah, I smoked the molds, but the lighter was weak, so next time I might try matches and be more patient. I did have bullets to make, afterall :)
I've got a bottom pour pot. Leaks a little from time to time, but when I get in the rythym, I can fill the mold and knock'em out in good order.

Can't wait to test them on the range
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top