Sprue direction?

[Flintlock_bob]

I have always placed the sprue pointing down, makes sense with a patched RB so why not in a revolver.

The other day I was watching a Youtube video and the guy loaded the ball "sideways" so that much of the sprue would be shaved off. I don't know if he did it deliberately or just didn't care which way it goes in but it got me wondering if maybe it might make the ball "rounder" having more of the sprue shaved off?

I know it's kind of hard to tell if I get the sprue centered or not and how much would it effect the accuracy?

 

[Mean Gene]

I've always heard to load the sprue on top centered.

 

[Katahdin]

Mixed feelings on the spur placement. When the rifle is fired and the projectile starts down the barrel and spinning ,then leaves the barrel it continues to spin.How would the spur stay in the same attitude ?? I have not done extensive testing in this but it would be interesting if all of use just loaded and shot and recorded the results.Then we could compare and see if this is a myth or fact.
Not saying it is or isn't just reflecting and wondering.

 

[Larry Akers]

Harry Pope determined that the base of the bullet was the main factor of accurate flight and must be perfect. The shape or condition of the nose wasn't important. That is why he always muzzle-loaded his bullets. That is why I load a RB with the sprue up.

 

[M. De Land]

I don't think much comparison can be made to the flight characteristics of a round ball and conical bullet as their shapes and thus reactions to the powder thrust and air are so entirely different.
The Bevel Bros in Muzzle Blast magazine did a test a few years ago,if my memory serves me correctly, of testing between spru up or spru down and could detect no difference in accuracy as long as the spru was centered.

 

[Zonie]

That is what I recall of that Bevel Brothers writeup.

The location of the sprue when they loaded their rifle didn't make a measurable difference in where the ball hit.

 

[Flintlock_bob]

In that case I think I will try loading them sprue up since it will be easy to see if it is centered. Unless I spend too much time fiddling with them. :grin:

 

[nhmoose]

The Bevel B's don't shoot good enough to tell a diff IMHO.

Years of bench rest competition showed sprue up won medals down did not.

In my guns using a false muzzle and bore size ball the sprue was gone upon loading.

In my benched non false muzzle squirrel match rifle sprue up was more accurate as seeing where the sprue was beat not seeing it on the base when loaded.

In shooting the base of the ball or bullet has proven to be more important than the front.

Shoot them anyway you want not on me whether they work or not it is a free country right now.

 

[M. De Land]

I started a few years ago to tumble my Lee molded lead balls to make the spru almost disappear but never felt I was getting the best from them unless I loaded the spru up and centered so all the tumbling did was make the sprus harder to find.
I quit tumbling the balls.

 

[Wes/Tex]

Agree...sprue up all the :wink: :haha: time!

 

[dickydalton]

I double-dog dare you to tell me that you have the sprue centered perfectly every time! :blah:

 

[crockett]

In "Six Guns By Keith" Elmer Keith recommended loading the sprue up, he claimed the flat sprue area would hit harder- like a SWC versus a RN. At regular pistol range the accuracy doesn't seem to make a difference although having the sprue deliberately sideways would seem bad. If you are just an accuracy nut maybe drill out the rammer and fill with epoxy and then set a greased conical or sprue/ball into it for a better alignment in ramming.

 

[Wes/Tex]

Ole Elmer had some pretty in-grained ideas, most from personal experience and pretty much on-point. Some, however, have been proven not so pointy! Still, the man will always be a good source of ideas on handgun shooting. Got to meet him a couple times and he was hoot to visit with...no lack of personal views! :thumbsup:

 

[rodwha]

You are quite the lucky fellow Wes!

This is one reason I like my Lee RB molds. No real sprue to concern myself with.

 

[curator]

I believe the reason why sprue centered up being most accurate in a rifle (my experience too!) is that any void in the cast ball will be directly under the sprue. Centering it up makes it possible to ascertain the rotational force will be around any imperfection. Think of the problems caused by loosing one of your front tires' wheel balance weights at 60 MPH. Imperfections centered have little to no influence on the flight of the spinning ball. Obviously this has no bearing on smooth bores, where preventing spin yields the best accuracy.

 

[Billnpatti]

While I have no imperical data to prove my theory, I am of the opinion that it will make absolutely no difference how you place the sprue when you load. Here's my unproven theory: When the ball spins, if there is a sprue of any significance, it will create a heavy spot on the ball. As the ball spins, the centripetal force of the spin will cause the heavy spot to move to the outer edge of the spinning ball. In other words, the spinning ball will always orient the sprue to the outer edge no matter how you position it when you load it, up, down, sideways, it simply won't matter. Just think about it. Let's assume you have a rifle with a 1:66 twist rate and you are firing a ball at 1500 ft/sec. If you do the calculations, you will find that the ball is spinning at 16,364 RPM. That will generate a lot of force to move the heavy spot to the outside edge of the rotating ball.

I think the secret is to cast carefully so as to avoid forming voids in the ball and use a mold that leaves a minimal sprue. I like the Lee molds because of the lack of a significant sprue on the cast balls. Even so, I tumble my newly cast balls to remove all traces of a sprue. My tumbled balls look like ball bearings when they come out of the tumbler.

That's just my theory and my way of doing things. It ain't the only theory or way of doing things, just mine......but I'm willing to share it. You're welcome. :thumbsup:

 

[Claude Mathis]

I have always placed the sprue pointing down, makes sense with a patched RB...

I know it's kind of hard to tell if I get the sprue centered or not

I would think that if someone was concerned about centering the sprue, placing it down would be problematic, because you can't see if it's centered? Would not placing it up give you a better look at it's position?

 

[crockett]

Before someone told me to have the sprue up I loaded it down- it made sense as it would be sort of a rudder on the spinning ball.

 

[M. De Land]

A rudder would make sense if the ball were not spinning just as it does on a ship or airplane but in a high speed spin it becomes and impediment especially if off center.

 

[Mr. Troll]

You guys got me interested in just what happens with the sprue direction. I've always pointed it up when I use cast balls, so I've never given it any thought. I went out to the range today with my '58 Remington and my M-1-22 Carbine. I have .451 cast balls and .451 swaged Hornady balls, so I figured this could be a good chance to see what happens. I took the Remington because it's the most consistent and accurate piece I have. Loads were 30 gr APP, and either 138 gr swaged or 138 gr cast. The distance was 25 yards, shot from a bench rest. There is a little inconsistency with the powder charge, I'm thinking because of the coarse grain of the APP. They all looked the same, but some didn't "feel" the same. The big thing I noticed with the sprue sideways was it was harder to ram them down, and they didn't feel the same level of compression. After I shot a cylinder of each, I played with the carbine for a while, and then went back and shot 5 more with the Hornady balls, just to see if it was a fouling build up issue, or not.... https://goo.gl/photos/y6vDmzw9J5KKD4KG8
I guess I'll be putting the sprue up all the time, like I have been!