Lead balls have casting imperfections

[tenngun]

Lead is soft. The force of starting and then ramming the ball home does much to flatten the ball top
Smoothbores open up after fifty yards, rifles after hundred. These longer rangers mild accuracy helpers pay off.
As most of our shooting is in those range limits any advantage by what you do with the ball are offset by other factors. In practical use sprue up or down won’t make a visible difference

 

[Historical Armsmaker]

Honestly my cast balls with a sprue shoot just as good if not better than swagged store bought round balls. In rifles I load sprue up.

Excellent response. After helping my dad, then running the business for 30 years, winning competitions all along the way, a 'minimal' sprue which has been cut off as low as possible with the mold, gets pounded right back into the ball. I agree with the ball flight being effected if it's not trimmed, but using a starter with a good concaved brass or bone starter goes a long way in negating the turbulence. By the way, the whole accuracy thing is a consistent ball in shape, weight, and load. Practice, practice, practice!!! And not just the shot!
Years to fine tune the process. The old ways are BEST!

 

[hawkeye2]

There is a whole lot of theory and opinion here with no documentation to back it up. I'd like to see some photos of groups with sprue up and sprue down shot with the same controlled conditions and equipment. Not that I doubt anyone but show us some proof. If I wasn't so lazy I'd do it myself.

Among the many myths, rumors and other things related to muzzleloading shooting the Bevel Brothers (Bevel Up & Bevel Down) researched was this one. They did extensive testing and published their findings In Muzzle Blasts many years ago. It would be great if someone could locate the article. My stash of the magazines is long gone.

 

[BadDaditood]

Sprue up makes for better hollow points- that’s what I call them when I forget the powder

 

[Ohio Rusty]

Among the many myths, rumors and other things related to muzzleloading shooting the Bevel Brothers (Bevel Up & Bevel Down) researched was this one. They did extensive testing and published their findings In Muzzle Blasts many years ago. It would be great if someone could locate the article. My stash of the magazines is long gone.

I have that printed article somewhere. What I took away most from the article was the effect of a void/bubble in the round ball causing the ball to fly off center. It probably acts like a knuckle ball inflight. It is because of that article that I pour my ball and continue to pour and overflow the molten lead to keep the sprue hot to help any trapped air escape through the sprue. I still weight my ball to make sure I have the best ball I can cast.
Ohio Rusty ><>

 

[bpd303]

I pour my ball and continue to pour and overflow the molten lead to keep the sprue hot to help any trapped air escape through the sprue.

That's the secret most casters take a while to figure out, when lead cools it shrinks and the sprue needs to be full.

 

[Rob M.]

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

....if you try sprue down just keep that sprue centered ! It can get off the side and dig into the bore then ...stuck. I learned the hard way decades ago . I'll never put sprue down again ! Have fun !

 

[deerstalkert]

....if you try sprue down just keep that sprue centered ! It can get off the side and dig into the bore then ...stuck. I learned the hard way decades ago . I'll never put sprue down again ! Have fun !

this has been the main reason taught to newbies for my whole life. the sprue up will disappear upon loading. sprue down has little or no effect. sprue sideways will either result in a stuck ball or very tough loading.
JM .002$

 

[J. Paul]

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

In muzzle Blast magazine about 15 to 20 years ago they did a test by drilling halfway into ball then loading hole up, hole down then hole sideways for several each position. Their conclusions were that sprue up or down didn't make any difference because from a rifle the ball would rotate around its center of mass to stabilize and made minimal difference for shooting unless needing maximum accuracy for scoring paper

 

[sheriff john]

We're talking about a round ball, not a cylindrical bullet. There is no "tip" nor "back end" of a sphere. The more perfectly round, devoid of air bubbles within, and consistently loaded - the more likely to have the same results with each shot (minus human error).

A guy can roll lead balls between two heavy metal plates to smash out minor imperfections if you've nothing better to do. I tried that twice. Boring and didn't really work well if the sprues/imperfections were very large. WTH?

Big ol' smoothbore pistol is not a precision gun. Minute of barn door accuracy on a good day. Have Fun no matter what anyone says!!

 

[deerstalkert]

the biggest detriment to accuracy with a prb is me. i have a .54 full length Hawken flint i just finished that i can feed some of the nastiest wrinkled balls and it will put them on top of each other, if i am out of the equation. i hate lead sleds as they break stocks but they remove me and i can tell how the rifle really shoots. handy when selling the gun to show its true potential.