Cast your own, shrinkage?

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Gooddaytoya!

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I just read that if I consider buying a ball mold I have to consider how much the ball shrinks as it cools. I never thought of that one before. Does anyone know if there is measurable or significant shrinkage in a cast ball is small as . 590? I can imagine that if I cast a 2 lb cannonball that shrinking is obviously reasonably to be expected. But with a.590??
 

Gooddaytoya!

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The companies have taken this into account & their moulds are calibrated to be the correct size after cooling if you use pure lead.
Thanks guys that's a relief. If I buy a mold I want it to produce .590 balls and not some unpredictably smaller size. I'll be using pure lead. And I get it that patch thickness plays a part. It looks like I'll be the proud owner of a new . 590 mold. Only 25 pounds English. It looks like I'll be starting with a 0.03 or .035 patch. The combination sounds reasonable to me as it a start, how about you guys?
 

cositrike

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If your barrel is around .610, I would have gone for a .600 ball and a 15 thou patch. That’s just my opinion and worth what I charge for it. Lol
 

Daveboone

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this is bizarre, but my cast bullets from a relatively new ( 700 rounds or so cast) .530 Lyman die, actually cool to a couple thousands larger....531 to .532, (compared to Hornady .530 balls which measure dead on) which my rifle likes!
 

oldwood

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Have cast bullets and balls for 60yrs.. In general , Lyman molds might not cast accurate dimensions , like perhaps up to .003 larger than do Lee molds. If I can help it , I have mostly gone to Lee for round balls molds.
 

nkbj

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My Lee ".600" mold dropped balls at .603" diameter.
So I found a .595" round ball mold.
 

mooman76

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this is bizarre, but my cast bullets from a relatively new ( 700 rounds or so cast) .530 Lyman die, actually cool to a couple thousands larger....531 to .532, (compared to Hornady .530 balls which measure dead on) which my rifle likes!
Lead with any alloy in it, will cool .001/2 larger. Are you sure your lead is pure? The Lyman usually run smaller than advertised if not right on, because of the cherry cutter wear.
 

Gunny5821

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My Lee ".600" mold dropped balls at .603" diameter.
So I found a .595" round ball mold.
Just bought a Lee .600 mold a couple of months ago and it consistently drops pure lead balls at .607 and every once in a while I get a .608 ball, maybe 1 out of 10. If the lead I used has any alloy in it, its not much, you can scratch it with your thumbnail just as deep as a swaged Hornady ball.
 

RobWheeler

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Sterling silver shrinks ABOUT 2% when it freezes from liquid to solid. Lead will have a number also.

rob
 

hanshi

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I use mostly Lee molds for round ball. The dbl cavity .440" Lee is what I normally cast for my .45s. I also have a single cavity Lyman mold for a .445" ball. But the Lyman drops ball averaging .443". The exact ball size is mostly irrelevant as the ball is patched and loaded. Incidentally, both the Lee .440" and the Lyman .443" load, shoot exactly the same: same velocity and same accuracy.
 

oldwood

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Graphite mold release agent , used sparingly , will prevent stuck balls for the most part.......... .....:ghostly: Please stay outa the gutters. This is a serious problem guys.
 
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