AJC1
Member
When casting what is the key to preventing tear out on the base of the bullets. Is it a timing thing where cutting sooner is better. Is it a sprue plate speed thing where hitting the plate is better than hand cutting. What's the scoop.
There must be an early and late window. If I cut it today right as it went solid it was super easy and no tear out. It also worked to wait a long time but then I had to use my rawhide hammer because I could not cut it by hand. The middle zone seems to be the problem.As the lead cools, it seems to go through a brittle stage where it fractures instead of cuts. Let the mold cool a bit more before cutting the sprue plate.
The one thing I know for sure is each mold acts differently. I've only used 3 and two were lee aluminum. This steel mold holds a lot more heat and I have to pump the breaks and slow down a lot. The lee is full speed to keep the heat in.I have a 10lb LEE pot too. I invited a friend to help a few weeks ago. One was casting. The other was feeding scraps of lead into the pot. We kept a steady pace while watching the temperature. With the pot on High, we were able to keep the lead level up while casting a steady stream of bullets.
With 1lb ingots, I cast until close to empty and then refill the pot. Casting halts until everything melts and comes up to temperature again.
Makes sense. My molds are LEE aluminum. They do cool down quickly and can turn out volumes of bullets quickly.The one thing I know for sure is each mold acts differently. I've only used 3 and two were lee aluminum. This steel mold holds a lot more heat and I have to pump the breaks and slow down a lot. The lee is full speed to keep the heat in.
There must be an early and late window.
Definitely had that on my lee molds. After cleaning up that mess I refuse to cut to early. Solid sprue plus 5 seconds minimumThere is, too early and it will smear.
I'm happy to have you guys around, seems books dont cover it all. Do track mold temp or do you just use lead as an indicator.The tear thing is three fold. One is the lead hasn't "set" completely by cooling down. Another is the mold is too hot. And the last is it may not have filled the mold completely. To solve any of these issues: You should be over-pouring your mold so there is a puddle of lead covering the sprue hole. As the lead begins to cool it will suck a bit more into the mold. Watch that lead on top of the mold. You can actually see it slightly turn color. It's almost like watching Jack Frost in the winter. The lead puddle will turn from bright silver to a dull silver gray color and you will see it freeze up. I use Lee and they can get too hot too. At a good temperature about 5 seconds after the "freeze". Too hot 10 to maybe 15 seconds. If bullets are fracturing, that is usually too much tin or zinc in the mix.
Definitely had that on my lee molds. After cleaning up that mess I refuse to cut to early. Solid sprue plus 5 seconds minimum
I have a Lyman thermometer in the lead pot and try to keep the molten lead around 750 degrees. Once the mold gets up to temp (bullets fill out and look good), I go at a steady pace, pouring and dumping. I can tell the mold is getting too hot when it takes longer than a 5 seconds for the pools of lead on top of the sprue plate to harden. At this point, I slow down my pace. On my 6-cavity LEE 356-120-TC and 356-125-2R molds, I look for the sprue to harden in 3-4 seconds. Any faster than that, I sometimes don't get consistent fills. Any longer than that, lead may smear when cutting the sprue and the bullets don't drop out as easy.I'm happy to have you guys around, seems books dont cover it all. Do track mold temp or do you just use lead as an indicator.