Cast bullet weight

[JohnD]

Hope someone can help me with a problem I'm having. I'm fairly new to casting. I seem to be able to make some nice bullets but the weight varies quite a bit on the batch. Is it something I'm doing or not doing? Some of my bullets vary by 2 or 3 grains. I'm using 92-6-2 lead.

Thanks JohnD

[7br]

Assuming that you are using the same alloy everytime, I would guess that your casting temp is varying. Someone correct me if I am wrong, but the hotter the molten metal, the more it should expand. The higher the casting temp, the lighter the bullet should be. Also note that the final size of the bullet should be less. Another thing to consider is that your blocks will be changing temp also. Probably less of a variable as the temp of the melt though.

Next question is how heavy of a bullet are you casting? For a 235gr .41 boolet, we would be looking at less than 1 percent variation. If we are talking about a 45grain 22 bullet, that is about 4percent.

[1Shirt]

Howdy, Sounds to me like a number of things, most of which come down to lack of consistancy in your process of casting. If your temp is consistant(and as suggested, that may be your problem) then control of temp may be your first area to look at. You didn't say if you were dipping or casting from a bottom pour. Either way, if your temp is consistant, then your technique of handling the mold must remain constant. Regardless, I recommend that you cast HOT. I have always had my best results with bullets that were at least slightly frosted, and have found these to be most consistant. One other factor may be how clean your material is, and if you are fluxing adequately and possibly as frequently as needed. To me being consistant has always been the key to casting good bullets, but even with the most consistant process, there will always be a small percentage of what I have cast above and below the average weights. Good luck!
1Shirt :coffee:

[Wayne Smith]

I had the same problem, and then I got a lead thermometer. I'm dipping from a 20lb pot, and when I keep the temps reasonably uniform the bullets are the same.

[JohnD]

My temperature has varied, I didn't know it was that important. I'll keep an eye on it from here on in. I have a bottom pour Lee 20 4. Thought I was fluxing pretty good but I may not be. How often should I flux and what temp do I want the lead at?

Not sure how accurate the thermostat on the Lee is though. I did just order a Magma Master Pot, that will probably be more accurate.

[wills]

Article by trapdoor84

http://users.ev1.net/~printolive/reg01.htm

[David R]

If it is a lee pot, try turning it all the way up, then cast some boolits. When they come out frosted looking, back off on your speed or the temp of the pot. I shoot for a galvanized look, not shiny, but not frosted.

When you do get frosted boolets, your mold is now hot enough.

Frosted boolits have a much better ES than shiny ones for me.

Try it and good luck. You will only get better.

David