Hi,
I was gone for a minute and returned only to find some of us are in desperate need of the following information:
Cast bullet weight depends on several factors: Alloy composition (the more lead in the mix the heavier the bullet), mold cavity size (obviously), and this little thing we all know as consistency. How tight the two halves of the mold are held against one another affects the size of the cavity which in turn affects the size of the bullet which in turn affects the bullet weight. So, if you hold the mold real tight, the bullet will cast smaller if you hold the mold loosely.
This also applies to automated casting. While mold pressure is prolly more consistent due to the mechanical leverage of the machine, sometimes a piece of lead gets stuck inbetween the two mold halves causing a gap between them. This will cause the mold to cast large bullets. When this happens, often we will see fins on the bullets. But sometimes the gap is so slight the defect is undetectable, visually anyway.
You cannot expect a commercial caster to weigh every bullet, not for $80 per thousand. That's our job as reloaders.
Finally, having the latest copy of QuickLoad and 18 years of reloading experience I can assure everyone that a 10% weight variance will not cause any pressure concerns. Bullet weight means nothing in the greater scheme of variables. Seating depth, case volume, powder charge weight, and bullet jump are far more important.
I have bought some bullets from Missouri. They are good bullets. I have weighed them and observed 7-10 gr variance, but I also know it means absolutely nothing. Not on paper and not internally. I purposefully assembled the heaviest and lightest bullets and shot them for groups off the bench. There was no difference on paper, and this was from a match grade 1911.
If you want perfection for $80 a thousand, get a single cavity mold and cast your own. Otherwise, find a different planet to live on.
I was gone for a minute and returned only to find some of us are in desperate need of the following information:
Cast bullet weight depends on several factors: Alloy composition (the more lead in the mix the heavier the bullet), mold cavity size (obviously), and this little thing we all know as consistency. How tight the two halves of the mold are held against one another affects the size of the cavity which in turn affects the size of the bullet which in turn affects the bullet weight. So, if you hold the mold real tight, the bullet will cast smaller if you hold the mold loosely.
This also applies to automated casting. While mold pressure is prolly more consistent due to the mechanical leverage of the machine, sometimes a piece of lead gets stuck inbetween the two mold halves causing a gap between them. This will cause the mold to cast large bullets. When this happens, often we will see fins on the bullets. But sometimes the gap is so slight the defect is undetectable, visually anyway.
You cannot expect a commercial caster to weigh every bullet, not for $80 per thousand. That's our job as reloaders.
Finally, having the latest copy of QuickLoad and 18 years of reloading experience I can assure everyone that a 10% weight variance will not cause any pressure concerns. Bullet weight means nothing in the greater scheme of variables. Seating depth, case volume, powder charge weight, and bullet jump are far more important.
I have bought some bullets from Missouri. They are good bullets. I have weighed them and observed 7-10 gr variance, but I also know it means absolutely nothing. Not on paper and not internally. I purposefully assembled the heaviest and lightest bullets and shot them for groups off the bench. There was no difference on paper, and this was from a match grade 1911.
If you want perfection for $80 a thousand, get a single cavity mold and cast your own. Otherwise, find a different planet to live on.
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