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blaser.306
12-31-2013, 11:46 AM
I have a mould that was cut for me by Tom @ Accurate, it is a 431-265c. I cast around 2000 boolits las spring / summer and now find taht I am out:( I had a pot full of alloy and I am new to using a hotplate for pre-heating my blocks ? The mould is brass and the slugs I cast last summer I was sizing to .432" with a weight of right on the dot 265 gr with WW alloy. This pot running @ 675degr. and the mould pre heated to 375deg. While casting a beautifull specimen, shiney with no frosting and perfectly filled out and round. They are dropping @ .4245" .425" and almost exactly 7gr under target weight. Any thoughts what I may have done to this pot of alloy, should I just toss it or "water it down" with another batch of WW in the spring. Thanks in advance for any thoughts / sugestions.
Doc_Stihl
12-31-2013, 11:51 AM
.425?? Doesn't sound plausable. How are you measuring the bullet diameter?
Do you have another mold handy that you could cast some to compare with a known?
blaser.306
12-31-2013, 11:56 AM
.425?? Doesn't sound plausable. How are you measuring the bullet diameter?
Do you have another mold handy that you could cast some to compare with a known?

The boolits were measured with the same digital caliper that I used before, and I do know that digi verniers are oly rely accurate to = -1 thou but close to 7? I have already drained all of the mystery alloy from the pot and will do some test casting with another mould when I have got some of my stocks back up to a comfy level.
merlin101
12-31-2013, 05:54 PM
This might be a stupid question but, did you zero the caliper before useing it?
The lighter boolit could because of a lighter alloy (less lead more tin= lighter) but it shouldn't cause your boolits to shrink.
blaser.306
12-31-2013, 06:09 PM
Not a stupid question! I did zero the caliper , however I am goung to check under some magnification for any burr that may be present. Other than that I have no explanation of how a boolit from a known muld would all of a sudden star casting that much undersize and weight????
blaser.306
12-31-2013, 06:57 PM
Dilemma solved!!! A combination of a small burr and stupidity with a bunch of tin added for good measure!!! Everyone have a great, safe and happy new year!