Cast Bullets -General information
Lets say I did cast some bullets of lead, do you have to run them through a sizer? Is lube really needed for the sizing? For example, if the mold is .357, why run them through a sizer at all?
No sizing with some of Lee's tumble lube moulds. These are lubed with liquid alox. Your alloy will give you different size bullets as the drop from the mould. High % of lead, smaller diameter. High % of antimony larger in diameter.
Do you really have to pay attention to bullet hardness, if say you were using tire weights as your lead? I sure don't want leading in my barrel(s)
2% tin in the alloy will keep bullets from leading. Water dropping will harden the bullets, but heat treating in an oven is a better process. Cast Bullets- General Information
Casting bullets
Bullet Sizes & Weights – How to Vary Them
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if you bullets drop from the mould undersize using 50/50 -WW& Pure Lead, you will need to add more wheel weight to increase there diameter. Lead shrinks more as it cools in the mould then wheel weights. Linotype can be added to increase bullet diameter also.
Quote:
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 .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
from 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 Cast Bullets
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Water dropping of bullets was invented to reduce the amout of costly alloys using tin and antimony. United States Patent 5464487
http://www.freepatentsonline.com/5464487.htmlI fine water dropping to be a waste of time when casting bullets with the proper alloy. Water and hot alloy can explode it they come in contact with each other. "While antimony is used to harden the bullet, the mixture of tin is critical, for while antimony mixes with lead in its molten state, it will not remain mixed when it solidifies. If tin were not added, we would have pure antimony crystals surrounded by pure lead. A bullet of this type , while it feels hard , would certainly lead the bore and eliminate all potential for accuracy. In a lead-tin-antimony mixture, the antimony crystals will be present just the same, but they will be imbedded in a lead-tin mixutre. As the bullet cools the tin will form around the antimony-lead keeping your bullets from leading the bore." I have read that this process can take up to 24 hours as the alloy oxidizes. If your going to size a cast bullet, wait 1 day. Plain base bullets to 1400fps, gas checked to 2200fps without leading. Check Lee lead testing chat for the maximum pressure allowed for you alloy hardness. Also us the formula > Bullet's BHN x 1422 = Pounds per square inch.
http://en.wikipedia.org/wiki/Obturate Cast alloy bullets should never Obturate. The bullet is sized over groove diameter by .0005" to .001" Some rifles will like as much as .003" over groove diameter. Casting bullets is really simple most times. If the bullet diameter is correct as it drops for the mould, you are good to go. Pure lead will be undersize in diameter, unless using a BP mould. High antimony will be on the large size. Always make sure you have 2 % tin in the alloy and you will never have leading. 22LR bullet have little to no tin and only 3 % antimony at the most. They some how don't lead the bore. This is where a very good lube is needed. Bullets i have cast over 30+ years without water dropping.
