"Glassing" cast round balls

[Tumblernotch]

I didn't think it would be a spliting of the ways BPS,

There's alot to be said about the confindence factor in all shooting and especialy target stuff.

When I cast, if the sprue plate is a little loose or if it's not lubbed proper an the sprue cut is a bit tipped the ball is scrapped. I actually weigh ball to tighter tolerance than most do.
Is it needed? Probably not, but I know it's not my ball that causes any error.
I tried several times tumbling ball in my Thumblers to remove the sprue mark, kinda noisy but it works.
In the end I found it didn't matter for my shooting, that I actually felt better being able to see the sprue and put it up,,

I always load sprue up. Since I load a little tight in all my rifles for target shooting I use shortstarters that set the balls about 1/8" below the muzzle before cutting the patch. They're milled concave to the same profile as the ball and remove the sprue as they are hammered. There has been talk that often there is a void just under the sprue area and I have seen a few in the past. I believe, though I haven't cut any to verify one way or the other, that mashing the sprue with the starter may close a void if it is near the surface. It would have to be very near I would think. At any rate, I only allow 1/10th of a grain +- variance in my target balls.

 

[Kentuckywindage]

the flat spot my lee mold leaves looks like the flat spot the ramrod makes after i push the ball down the bore. A waste of time IMO.

 

[David W.]

The Bevel Brothers did an article on sprue placement. They said it makes no difference sprue up or down. Boy, I miss their articles!

Some moulds have no sprue cut off what so ever and people seem to shoot them accurately.

 

[nkbj]

I drive an average of about 110 miles a day.
99 cent store high sided metal cake pans that I use for bullet trays work in the turtle hull just fine for rolling balls. A week in the pan and sprues are gone and a wrinkle will almost disappear.
Cookie sheets work OK but .60 and .68 balls sometimes jump out.
Now, to my way of thinking, here's the corker... The sprue metal has to go some where and the ball will not be as nearly spherical as when it dropped out of the mold. So, if you're sweating over a patch thickness that works best why introduce diameter changes in the balls?
.60 caliber balls can have as much as a .003" uneveness (measurement difference from one spot to another) after the sprue is rolled away. So, the bad balls get rolled for the .62 smoothy and the good balls get loaded sprue up in the rifle.

 

[Naphtali]

I first saw this process done in 1992, by a prototype maker for Boeing. In a previous life he had been the gunsmith, tool maker, prototype maker for Frank Straight.

The rifle was a Ferguson .58-caliber "deerstalker" he had built. He rolled cast bullets between his granite surface plate and plate glass. His procedure took less than five minutes per bunch of balls. When we went to his backyard range, he put on a memorable demonstration - nine shots in 60 seconds. Of course, he was not aiming, and he arranged reloading stuff on his shooting bench. Nevertheless, nine shots in 60 seconds.
***
When he shot for accuracy, five-shot groups at (I remember??) 80 yards were about three inches. This was off-hand with well-made open sight system. I did not shoot this well.
***
Somewhere in my archives I may have photographs of the rifle. Despite being a prototype, it was among the most aesthetically pleasing rifles I've experienced. . . . Yeah, I asked him to build one for me. But he said he was no longer building flintlocks for sale. . . . Oh, well.

Sorry about the yammering reply. Hope something in here helps.

 

[nessmuk]

I have never been offended by the spru. :idunno:

+1 on that.

 

[irishtoo]

cheap rock tumbler, two hours later no spue