One casting session, different bool it weights, why

[Ghost101]

Well the title kind of says it all. I casted from a Lyman .452651BV mold. Suppose to be 330 gr. They are all over the place in weight, from 326-347. I try to keep the temp in the pot between 650-700. The metal was WW with a little bit of tin added. Water dropped. Can't remember if I used a ladle or if they were bottom poured. It doesn't matter what mold this is for, I just need to know what causes this flux in weights in any casting session so I get cure the problem
Funny I got this mold for a .450 bushmaster round but have not found any powder loading info for it. Still looking.
I will try in my Ruger revolver, old style Vaqeuro.

[243winxb]

Temperature fluctuations is my guess.

[Ghost101]

Kind of what I was thinking, but wasn'to sure. Does anyone havE " PID " units for sell ? I've read the post on them but its beyond my talents to make one.

[captaint]

That's a pretty wide variation. First, I would check diameters. If some of the boolits are fatter, maybe your mold is not closing completely. Are we using a 6 cav Lee mold ?? Mike OK. Just saw it's not a Lee mold. Check diameters anyway.

[Wayne Smith]

Check the light ones for voids. I'll bet that they are from early in your casting and that the sprue solidified too early. Temperature fluctuations will cause weight differences but not that much.

[1Shirt]

I would go with Wayne!
1Shirt!

[44man]

I go with voids too. It is why I never depend on a boolit to take metal from the sprue.

[243winxb]

Voids, is a better answer. Cast hotter.

[bhn22]

Voids, is a better answer. Cast hotter.

And at the fastest pace you can manage without smearing lead on the sprue plate. The consistent temps you really seek are at the mold itself. I normally cast with two molds that are as close in weight in diameter as I can find. One they're both hot, you'll see a lot of production going on.

[GLL]

By any chance are you using an electronic scale ?
If so, try weighing the same bullet 25 times.

Jerry

[Ghost101]

I am using an electronic scale, Dillon. I will be cutting up the lighter boolits to check them out.
What is the prime temp for a mold?
Thank You

Ghost101

[Echo]

I believe Swede N. of NOE said that the mold temp should be around 300*, and will prepare the molds he sells for a sensor insertion so you can monitor mold temp.

[Ghost101]

I was able to go to my reloading room this afternoon. Checked my Dillon electric scale 30 times with the same boolit. Same results every time. Check it out with my RCBS balance beam an there was a tenth, .01, difference between it an the Dillon. Maybe I just got lucky with the electronic scale. I'm trying to learn as much as I can with the Lee, Lyman an RCBS molds before I go out an get some fancy molds, but will try an check them out on the webb. A sensor in the mold sounds pretty kool .
Just got a complete set of pin gauges off of ebay today. Had bought some individual ones some time ago. Going to jump into checking out the chambers on my revolvers to see if I need to enlarge them. Have already slugged the bore's several times. Never used a micrometer before I started casting. I had several friends show me how to use them an clean them. Thank God I'm not to old or to smart to start learning again.

[Larry Gibson]

Casting temp too low and not getting the alloy into the mould fast enough. 715-735 is what I use (thermometer). That is a big bullet and the alloy cools very quickly and begins to solidify as soon as it hits the mould. If you don't get the alloy into the cavity quickly enough voids, wrinkles and pour fill out result with the attendant large weight variations.

Either use a bottom pour with the spout wide open or ladle pour with a good proper ladle (Lyman, RCBS or Rowell) using the proper technique with each. As mentioned be very generous with the sprue.

Larry Gibson

[Ghost101]

Thank you Larry. I still want to stop by for some coffee some day. Check out your area. My mother, 94, has taken a bad turn a couple
of times this yr. I take care of her so I've been hanging around this place for now. But Havasu might be better for her, weather an altitude, over Prescott.

[gwpercle]

Just stop weighing them. I got a new scale and was fooling around with it and discovered the weight variations in boolits and started segregating them into different piles and loading them in like batches and was getting all osessive/compulsive abut it when I discovered it didn't matter . My groups were the same no matter how I did it. In theory groups should have improved but in practice they didn't.

Now I just cast them, inspect for defects and load.
No more weighing!

I do get better consistency by pressure casting with a ladle.
Gary