The Firearms Forum banner

Casting 4 cavity mold

2K views 22 replies 11 participants last post by  howlnmad 
#1 ·
Merry Christmas all,

My first attempt at a 4 cavity mold and gee wiz :confused:. Had a heck of a time breaking off the sprues. It was so darn hard that I just resorted to only filling the middle two cavities. I think my problem is that by the time I get the last cavity filled the first one or two have had time to cool off and harden :mad:. Anyone have some advice on making the task a little easier?
 
#4 ·
I use an old piece of hickory, or oak, and a hammer to "knock" the sprue off. I use both 2, and 6, cavity molds.
 
#5 ·
Using a four cavity mold is all about timing and temperature.
I do own a couple of them but in all honesty I don't like them.
I don't know if this is correct, but it works for me. What I normaly do with a 4cav. is to put the bottom of the mold right on the molten lead while it's still in the pot. This brings up the mold temperature to just a few degrees below the melting point of the lead. When poring the lead into the mold, wait until you see the contraction of lead on the spur. As soon as it stops contracting is when you knock off the spur. Then give it a few seconds and then open the molds to drop out the cast whatever. Then quickly refill the mold and do it all over again. If the cast is frosted then you are going to fast. And if it is hard to knock off then you are to slow.
 
#6 ·
I solved that problem years ago.
The mold must be kept hot and you can do this by heating it.
I use a duplex outlet box on a hot plate. Trim out one side enough for the mold to fit in.
Then attach the top. Place the duplex box on the hot plate and allow to heat up.
The fill with lead and use a dowel rod or small hammer handle to give it a bump to
trim the spure. I always place the mold back inside the box when adding lead to the pot or taking a break. No more wrinkled bullets and they're consistent.
 
#8 ·
Thanks for the input and helpful hints. I'll be sure to put them to use. Thinking about swinging by the hardware store and picking up a hickory ax handle. Kidding! Not sure when I'll be able to get back at it again, hopefully with in the next month and let you all know how things go.

Blessings
 
#11 ·
Thanks Doc. Sounds like the hot plate is really the way to go. I'll swing by the Salvation Army and Goodwill to see if they have one I can snag. I really appreciate the help. Being able to double my production would make me very happy.
 
#13 ·
That's the way I do it to.
 
#16 ·
I use a bottom pour, but have the ladle also. One trick I recently learned about the bottom pour is that after a while the stream of lead may get small, if that happens it can be fixed by raising the temp of the lead, or even reducing it some.
 
#15 ·
Is the mold new or used? I would think that if you sped up your casting the first cavities poured would not have time to cool "hard" before the last cavities are poured. Keeping the mold hotter will aid in slowing down too. I have also found that when casting with a "harder" alloy, mebbe 15 + BHN, cutting the sprue is more difficult. I would remove the sprue plate and using fine crocus cloth or emery paper, polish the underside of the plate (place crocus/emery on a flat surface, put the plate on the cloth and rub it back and forth), sharpening the sprue holes. I use a yellow plastic mallet, mebbe 8 oz. and that works perfect and will not damage any part of the mold if an OOPS! happens...
 
#17 ·
I'm using a ladle with a small opening/spout. I know the bullets I made are PLENTY hard. I put and ounce of Tin/Antimony solder with an ingot of wheel weights. Can't even scratch them with an awl. As I'm new to all this I'm guessing I have multiple problems causing my trouble. It's deffinately a skill that one learns by screwing up. At least that would be my guess. Keep it coming guys. I'm learning quite a bit with this conversation. BTW, I have read through and use as my reference the Lyman Cast Bullet Handbook 3rd Addition.
Thanks to all
 
#19 ·
From this info, I think I'd add some pure lead to the alloy, soften it up. I have never had a need for "hard cast" bullets as air cooled, 9-12 BHN have served me well for all my handgun shooting. I have reloaded my alloy in .44 Magnum to magnum velocities, guessing at 1,100+ fps in .44 and mebbe 1,200 fps in my .357, with no leading. Fit is the key, not hardness, for clean shooting lead bullets...

The only way to learn to cast bullets, is to cast bullets...
 
#18 ·
Also water quenching bullets is the way to go-it also adds a hardness factor.For non-leading-lubing enough is the secret,Elmer Keith was sending .44spec bullets at .44mag velocities with 11Brinnel bullets.
 
#20 ·
Sounds good. Now in this thread I've read a few times about Measuring the hardness of the bullets. Is there a specific gauge that Ya'll are using?
 
#22 ·
Thanks Howlnmad. I'm thinking I may have overdone it and the only way to find out is with this gizmo. My MO has always been if a little is good, more is better and a lot is best :confused:. Doesn't always work out to be a good thing. I think this is going to be a fun addition to my shooting fun.
 
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