Lee Loader

I guess I'm simple 'cause I always figgered different alloy equals a different weight... In my mind lead was the heaviest component and the things added to it (tin, arsenic, etc.) are lighter so the resulting "mix" would be lighter too. More lighter stuff, lighter bullets...

mikld wrote:I guess I'm simple 'cause I always figgered different alloy equals a different weight... In my mind lead was the heaviest component and the things added to it (tin, arsenic, etc.) are lighter so the resulting "mix" would be lighter too. More lighter stuff, lighter bullets...

That is true and the more on one thing added will make the lead harder to a point. More antimony will let the bullet drop bigger too but heat of the mold can help there too. Consider the mold haves as tow separate pieces that expand the same amount but because the cavity is in each half they will shrink when heated. Take the the same metal and drill a hole in it and that hole will get bigger. Cut the hole in half and now they get smaller.

Hope that was clearer than mud.

So a hot mold cast smaller or larger diameter?

62chevy wrote:

mikld wrote:I guess I'm simple 'cause I always figgered different alloy equals a different weight... In my mind lead was the heaviest component and the things added to it (tin, arsenic, etc.) are lighter so the resulting "mix" would be lighter too. More lighter stuff, lighter bullets...

That is true and the more on one thing added will make the lead harder to a point. More antimony will let the bullet drop bigger too but heat of the mold can help there too. Consider the mold haves as tow separate pieces that expand the same amount but because the cavity is in each half they will shrink when heated. Take the the same metal and drill a hole in it and that hole will get bigger. Cut the hole in half and now they get smaller.

Hope that was clearer than mud.

Thanks '62, but I've been a machinist/mechanic all my life and have cast bullets for about 18 years. Mold temperature, melt temperature alloy and even pouring method can have an efect on bullet size and weight...

jdl447 wrote:So a hot mold cast smaller or larger diameter?

That's a great question... at first one might think that since the mold has heat-expanded then the dropped bullet should be larger diameter... but it expanded in every direction, so it expanded into the cavity too... so the bullet should be ... smaller diameter.... hmmm....

Good question...

Then I've run across this:
"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"
http://www.redding-reloading.com/pages/ ... ights.html

and this...
"Using a Lee 255 grain swc mold 45 caliber I ran an experiment last night. Half the bullets I water dropped, the other half were air cooled. (one drop in the water, the next on the cloth) The water dropped seemed to be larger than the air cooled."