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BAGTIC
10-29-2010, 12:37 AM
Does anyone know where I could find info about the as cast variations in diameter due to the alloy used? Pure lead, #2, WW, Linotype, Monotype, zinc, etc.

fryboy
10-29-2010, 01:35 AM
the lyman cast book has a lil bit tho they only used a boolit or two ...and ;asc has three plus a bit of other stuff ..scroll down on this page

http://www.lasc.us/CastBulletNotes.htm

243winxb
10-29-2010, 11:24 AM
http://www.redding-reloading.com/index.php?option=com_content&view=article&id=88:bullet-moulds-charts


Bullet Sizes & Weights – How to Vary Them
The bullet diameters and weights presented in this list are based on the use of Taracorp’s Lawrence Magnum bullet alloy (2% tin, 6% antimony, 1/4% arsenic, 91.75% lead).

Bullet diameters and weights will vary considerably depending on the lead casting alloy used. This variation can be as much as 1/2% on the diameter, and 8% on the weight among the most commonly used casting alloys. For example, a .358-158 grain bullet might show a diameter variation of .002", and a 13 grain difference in weight.

Of the most commonly used alloys, wheel weights (.5% tin, 4% antimony, 95% lead) will produce bullets having the smallest diameter and heaviest weight, with such bullets running approximately 1/3% smaller in diameter and 3% heavier than bullets cast with Taracorp's metal. Linotype will produce bullets with the largest diameter and lightest weights. This alloy will produce bullets approximately 1/10% larger and 3% lighter than Taracorp. Other alloys of tin and antimony, with antimony content above 5%, will produce bullets with diameters and weights falling between those cast f rom wheel weights and linotype.

Alloys containing little or no antimony will cast considerably smaller than wheel weights and in some cases will produce bullets too small for adequate sizing.

Within the limitations given above, the weight and diameter of a cast bullet can be adjusted by varying the
alloy’s antimony content.

The size and weight of bullets of a given alloy will also vary according to casting temperature. Higher temperatures will result in greater shrinkage as the bullet cools, thereby producing a slightly smaller and lighter bullet than one cast of the same alloy at a lower temperature.
From Rotometals-

Basic Rules for Harding Lead-


For every 1% additional tin, Brinell hardness increases 0.3.
For every 1% additional antimony, Brinell hardness increases 0.9.
For a simple equation,
Brinell = 8.60 + ( 0.29 * Tin ) + ( 0.92 * Antimony )

runfiverun
10-29-2010, 12:49 PM
try page 58'ish of the lyman cast bullets book.
they have predicted and as cast diameters on about 15 or so boolits.
with 4-5 different alloys.