Molding my own round balls

Doc Hoy

New member
I have always cast my own bullets and have a fairly good assortment of molds

I am not a purist but I think I may be getting there.

Some of you may remember that a used pistol I bought, a .44 1851 Colt from Euroarms was in extremely good condition but could not be loaded owing to a defect in the cylinder. Finish reaming had not been done and so even bullets of .451 calibre would not fit. I finally bought a replacement cylinder from the Winchester Sutler (Great folks) and am still shooting the pistol.

Anyway this experience lead me to want to know more about the size of the bullets I was trying to use, so I started measuring them, first with a digital caiper and then with a Starret Micrometer. Also bought a scale and started weighing them.

What I learned is that the bullets I get from my molds are consistently larger than the mold marking by about two to three thousandths.

I admit that my caliper and micrometer could be off but the oversize is really not the issue. Of greater concern was that the balls were not of a consistent size. Ball diameter woudl fluxuate during a casting run by about four thosandths. So out of a .451 mold (Lyman) I would get diameters anywhere from .451 to about .455.

This seemed odd so I checked some Hornady .451 that I got with the pistol. Guess what!. They were all over the place too. .449 to .453.

So now I am trying to get scientific.

I made myself a bullet rack with a hole for each bullet as it comes out of the process. I numbered the holes inthe rack so that I know the sequence that the bullets come out of the mold.

I also designed a set of mold handles for my Lyman and Ideal molds that are fitted with a spring that holds them shut. My thought is that perhaps the inconcistency of diameter was coming from minor differences in the pressure I am applying with my hand as the bullet cools in the mold. So the spring applies the same pressure every time. I don't know if it is the right pressure, but at least it is the same pressure.

Here are the results.

I have two .454 round ball molds

One is a Lee with the handles that are not spring loaded.
The other is an Ideal which is fitted to the new spring loaded handles.

I cast runs of 42 balls.

From the Lee with non springloaded handles I begin to get consistent castings after about half a dozen balls. They start at about .455 with excessive defects and by the seventh or eight bullet they are up to .457 average diameter. The come out plus or minus 1 one thousandth so I get balls as low as .456 and as high .458.

From the Ideal mold I get good castings after about 15 balls. From then on the diameter of the balls fluxuates no more than 2 ten thousandths.

I don't know if the consistency is coming from the more consistent pressure of the spring loaded mold or from the fact that the Ideal mold is made of steel and the Lee is made of aluminum. But I can say this. When I used the .454 Ideal mold with standard handles I was getting the same amount of variation as I got from the Lee mold. I have a .451 Lyman mold and I got no better consistency with standard handles.

It took me about four hours to make these spring loaded handles and they do not fit my Lee molds.

Any comments?
 
Good report

Doc,
I applaud your ability to try and figure this out and get what you thought you "ought" to have gotten out of those molds in the first place.
Handle pressure sure sounds like the only variable in the equation.
I guess it is some relief that the balls were coming out at least a little larger rather than smaller-

One would think a ball mold would have been made by now that would have handles like say vice grips to apply consistent pressure.
Is that how you did your handles?
 
Two responses

To BLE,

I am convinced that the Lee (aluminum) mold fluxuate in temperature more wildly than the Lyman or Ideal molds. They come up to a stabile temperature more quickly (as indicated by the fact that consistent castings are reached after only six or seven bullets while the steel molds produce more than twice that many rejects.) So that says to me that they would cool and heat more quickly during the casting run.

To Oldfalguy,

Best way I can describe it is to mention the spring loaded clamps that they sell for about a buck and a half. You squeeze them and they open and let them go and they close.

The mold handles work the same way.

I'll take a picture and post it.
 
kbuck - Tnx

KBuck,

Thanks for the tip. As you infered from my post, my ultimate goal is removing the variations that destroy accuracy.

There are many things that I do that harm accuracy, but this is essentially my first more or less scientific attempt to get better.

Tnx, again for reading the post and responding.
 
I always thought swaging was the best method for making consistent lead balls. You don't have to worry about mold temperature or lead temperature (when its melted) or lead gases. However, I don't have the ducats to buy a press. :o
 
4V50 Gary

Yes...And in my case the cost is probably fifty percent of the reason I mold my own. Or at least it was. But I will tell you I have a revelation when I measured the Hornady .451 round balls and found they were plus and minus two thousandths.

I have no idea of the age of those Hornadys In fact the only reason I call them Hornadys is that they were in a Hornady box. They were spruless so they were likely a manufacturer's ball. But I would have expected better quality control. Does this hark back to our conversation about four cent percussion caps? Perhaps Mykeal has a comment.
 
Temperature Doc, Whether the mold is Aluminum or steel doesn't seem to matter. What does matter is the temperature of the mold. The lead temp should be stabilised by the pot. Put the mold on top of the pot so that it is the same temp as the lead. after pouring the lead should take a short time to solidify. If it takes too long the mold is too hot. If it solidifies to quickly the mold is too cold. It takes a while to get the rhythm down so that the mold is the same temp for each pour.

I realise that this is elementary information, but I have found that to get consistent results, the temp must be the same for all pours. The problem comes from shrinkage in the mold. Also I always drop my round balls into a tall can of cold water to get the shrinkage rate the same.

I have used Hornady balls in my .50 Hawken and have had pretty fair results with them. I am still in the process of tightening up my groups though.:)
 
To MacGille

I do the same (dropping the balls into water). I have a pad on the bottom of the cup (a one pint plastic cup that I get when we order Wonton from the Chinese joint down the street.) and the cup is filled with water. I made a little wooden tweezers for taking the bullets out of the water so I don't get my hands wet. (Droplets of water around a 600 degree lead pot is just too foolhearty for me). Before I was using this bullet rack that I described earlier, I took the bullets out of the water tub and put them right into the lube tub. Now I take them out of the water and put them on the rack so I can keep track of the order of the bullets in the run. I will probably find out that it is not necessary to be that finnicky. I agree with your comment on rythm. (This may be one case in which the rythm method does work.)
 
Castless Casting

How tall drop is required to produce spruneless round balls via the shot tower method?

Akeela
 
Dunno

But a shot tower in Virginia has a total drop of 150 feet. Phoenix shot tower in Baltimore is 234 feet tall.

I drop mine about six inches.

Tnx,

Doc
 
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