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Lead balls have casting imperfections

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Joined
Nov 26, 2023
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Kirkland, Washington
Hi - I just received the lead ball shot for my .62 cal Sea Service pistol. I notice the balls have some imperfections from the casting process (i'm sure there's a more correct term for this, but I don't know what it is). I'm new to flintlocks, so I don't know if this might cause problems. My question is, do I need to smooth these down or do anything before I shoot them? Photo attached showing the slightly raised circular raised area where the riser on the casting was cut off. Thanks for any advice you can give :)
 

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That's nothing to be concerned with, especially in a pistol. Just load them up and have fun. The flat area is called the sprue. It indicates that the ball came from a mold. Most folks here will say that it should be placed up when you load it but again, don't be too concerned with that either.
 
Sprue up, Sprue down, if you care about accuracy, Sprue Down. In the aerodynamics of the round ball, the "leading edge" needs to be as smooth as possible to cut down on flyers. The "trailing edge" is in a low pressure area, therefore any imperfections there will have less effect.
 
Hi - I just received the lead ball shot for my .62 cal Sea Service pistol. I notice the balls have some imperfections from the casting process (i'm sure there's a more correct term for this, but I don't know what it is). I'm new to flintlocks, so I don't know if this might cause problems. My question is, do I need to smooth these down or do anything before I shoot them? Photo attached showing the slightly raised circular raised area where the riser on the casting was cut off. Thanks for any advice you can give :)
I'd think that at "deck distance" accuracy doesn't need to be pinpoint! Sounds like a fun pistol to shoot!
 
Sprue up, Sprue down, if you care about accuracy, Sprue Down. In the aerodynamics of the round ball, the "leading edge" needs to be as smooth as possible to cut down on flyers. The "trailing edge" is in a low pressure area, therefore any imperfections there will have less effect.
Are you sure about that?
 
Those are ballistic tip round balls 🤣

Seriously, as others have said load sprue up and make some smoke.
 
I every accuracy trial I have ever read, the base of the bullet is the most important. I always load the sprue up. I once shot a 10 shot table match with hand cast balls with a good sized sprue, that had an average of .210” spread. That was sprue up. The tremendous pressure on the base of the ball would push it out of line if the sprue was off center. That would have much more effect on accuracy than a slightly off center sprue on the front.
 
I every accuracy trial I have ever read, the base of the bullet is the most important. I always load the sprue up. I once shot a 10 shot table match with hand cast balls with a good sized sprue, that had an average of .210” spread. That was sprue up. The tremendous pressure on the base of the ball would push it out of line if the sprue was off center. That would have much more effect on accuracy than a slightly off center sprue on the front.
But with the sprue up it contacts the wind first and off center a bit would it not create an off balance ball allowing it to exaggerate the lopsided spin and it to be effected and create a greater curveture in the arch of the roundball side to side? The pressure on the bottom of the ball would be the same virtually as the top of the ball thus push it out of line. The bottom of the ball is not in contact with the wind where as the top is and effected first and the most.
 
But with the sprue up it contacts the wind first and off center a bit would it not create an off balance ball allowing it to exaggerate the lopsided spin and it to be effected and create a greater curveture in the arch of the roundball side to side? The pressure on the bottom of the ball would be the same virtually as the top of the ball thus push it out of line. The bottom of the ball is not in contact with the wind where as the top is and effected first and the most.

The force of the propellant is the primary force on the ball. As Okawbow said every accuracy study I've read or demonstration I've seen has pointed to the base of the projectile as THE most important end of the projectile, especially in rifled guns. The projectile is stabilized by spin enough that the wind resistance on the nose has minimal effect on accuracy in comparison.

With some looking you can see this demonstrated on modern unmentionables on YouTube.
 
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The force of the propellant is the primary force on the ball. As Okawbow said every accuracy study I've read or demonstration I've seen has pointed to the base of the projectile as of THE most important end of the projectile, especially in rifled guns. The projectile is stabilized by spin enough that the wind resistance in the nose has minimal effect on accuracy.

With some looking you can see this demonstrated on modern unmentionables on YouTube.
And the result is called keyholing correct?
 
Wow! This is a fascinating discussion! As an engineer-type, I'll conduct some experiments and report back on the results, once I get it completely working (just got the flints and other accoutrements yesterday, but still haven't drilled the touch hole or gotten black powder). Happy to say the lock doesn't seem to need tuning, as it produces good sparks and completely opens the frizzen every time. Broke a flint, though.

For the experiments, I'll try (1) sprue down, (2) sprue up, and (3) sprue sideways - i.e., rubbing against the side of the barrel. My current thought is that the sprue rubbing against the side of the barrel might impart some spin to the ball, like a curve ball in baseball and cause it to spin off-course. But that may be completely wrong.

So here's something else I ran across the other day about high-powered rifles: I don't remember the term, but it has to do with the precision of the symmetry at the very end of the barrel - something about how a nick or imperfection in the end of the barrel can throw the bullet off-course as it's exiting the barrel. And then something about how the Army determined that an 11 degree taper at the end of the barrel was optimal ... So I'm wondering whether imperfections at the end of a flintlock barrel could be a cause of bad accuracy - ?

It will be fun to see what happens :)
 
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