Round Ball Tumbling With Graphite

[Pro Libertate]

I've been tumbling dry in a HF rock tumbler for years, works great, from the bench they shoot tighter groups than not tumbled.

I had these boxes of unopened .440 Speer round balls that I purchased from a pawn shop for $10. They appeared to be oxidized, possibly from the flux that was used? I tried tumbling the balls by themselves with unsatisfactory results. It was adding just a single squirt of dry graphite that resulted in the improvement seen in the upper box. Curiously enough, rubbing the balls vigorously between my fingers doesn’t result in any residue on my fingertips or any change in their sheen.

 

[deerstalkert]

We’ll now you’re just being silly!

The patch doesn’t stay with the ball the whole length of the barrel during firing, so I should think there’s plenty of opportunity for the ball’s lubricity to affect velocity. Even if this increase in speed is slight, who doesn’t want to achieve the most velocity they possibly can?

I’ve read that cannon barrels were once lined with graphite to improve ease of loading, but mine is only a theory. Using a chronograph on untumbled round balls versus tumbled without graphite and finally tumbled with graphite ought to settle any debate.

might have to disagree. i have found patched balls at 65 yards from the muzzle. seems they rode the ball the full length of the bore!

yes i was being silly with the teflon tape. though in years past i have used teflon tape for patching conical in cartridge loads. wouldn't recommend it.

 

[GBG]

I use an old cement mixer to tumble 25 lbs of cast buckshot at a time. Throw in a palm full of mechanical pencil graphite and tumble 24+ hours. They come out looking as good or better than commercial factory loaded buck. Patterns improve in both MLs and and modern guns. I think the graphite lubes and eases the shot passage through tighter than normal choke tubes in suppository guns, and reduces leading in ML smoothbores.

 

[Pro Libertate]

might have to disagree. i have found patched balls at 65 yards from the muzzle. seems they rode the ball the full length of the bore!

Interesting! Though one has to wonder if that isn’t more of an exception than a rule. In the slow motion videos I’ve taken of myself shooting my .45/.50 muzzleloaders, the patch breaks away rapidly after leaving the barrel. Then again, I tend towards a thinner patch.

I would think you’d want the ball to separate from the patch no later than when they exit the bore. If the patch is skitching a ride, you can bet it’s adversely affecting accuracy.

 

[ibud38]

It was suggested on a bullet casting forum that I try putting a squirt of dry graphite in with my round balls and allow them to tumble in a rock tumbler for a few hours. I opted to let these go overnight. During the casting process, some of my bullets ended up less than perfect, with small divots, casting and sprue marks left by the Lyman mold. This method resulted in balls that were perfectly round, with a shiny, hammered finish appearance. Give it a try— I think you’ll be most pleased with the results!

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If your loading bare balls the the graphite would be a good idea, if you are patching those balls it wont help one bit, better maybe to put the graphite on the patch where it will do more good. Otherwise it just improves the finish when tumbling.

 

[Piquant]

I've been tumbling them in my rock tumbler/ball mill for awhile. I don't use graphite just the balls. A 1/2 hour will remove the sprue and dimpled them like a golf ball. I find they are a little harder to load but will shoot damn well.

 

[longcruise]

I'm thinking it wouldn’t correct visible casting imperfections but might hide them.

Mine come out with no detectable sprue which I like because otherwise I struggle to center the sprue when loading and I'm too anal about it to ignore it

Interesting! Though one has to wonder if that isn’t more of an exception than a rule. In the slow motion videos I’ve taken of myself shooting my .45/.50 muzzleloaders, the patch breaks away rapidly after leaving the barrel. Then again, I tend towards a thinner patch.

I would think you’d want the ball to separate from the patch no later than when they exit the bore. If the patch is skitching a ride, you can bet it’s adversely affecting accuracy.

I think a ball with patch found down range wasn't shot from a rifle. Maybe if it was a dry ball shot out with a few grains of powder or maybe out of a smooth bore. Otherwise the ball is spinning at thousands of rpm and the patch is spun open by centrifugal force and blown off by the air stream. I've seen quite a few slo mo videos with that exact thing happening.

 

[SDSmlf]

Am I getting this correct? Tumbling with graphite removes the sprue, wrinkling voids, eliminates any weight variations along with lead oxide on the surface of the balls. Where does the oxide go? Does it just disappear? Does it return? Do you have any weigh data before and after tumbling?

 

[Pro Libertate]

Am I getting this correct? Tumbling with graphite removes the sprue, wrinkling voids, eliminates any weight variations along with lead oxide on the surface of the balls. Where does the oxide go? Does it just disappear? Does it return? Do you have any weigh data before and after tumbling?

I can attest to all these things; however, I -regrettably- cannot provide you with any data or scientific explanations as to how it is achieved. Insofar as the oxide is concerned, it’s too soon to tell. While I haven’t weighed balls before/after tumbling, I have measured them with a caliper, and the difference I’ve observed is negligible… perhaps one/two thousandths of an inch. Some of those I’ve measured after tumbling still come out to .735 (the mold’s spec).

 

[SDSmlf]

While I haven’t weighed balls before/after tumbling, I have measured them with a caliper, and the difference I’ve observed is negligible… perhaps one/two thousandths of an inch.

I don’t have a lot of data, but I have weighed .595” diameter lead balls at 317 grains and .600” diameter lead balls at 325 grains. If the diameter changes the weight changes in my experience. How does tumbling change the diameter of a lead ball without changing the weight? Or does it just change the diameter a few thousands and not change the weight?

 

[flconch53]

I've been tumbling them in my rock tumbler/ball mill for awhile. I don't use graphite just the balls. A 1/2 hour will remove the sprue and dimpled them like a golf ball. I find they are a little harder to load but will shoot damn well.

If you don't have a tumbler fill a coffee can half full and let them roll around in the back of your car. Takes a while but it works

 

[Frontstuffer070]

I made a wood box with a lid. I put the fresh cast balls in it and fill the bottom about half way, only one layer. Then I put that box that has a secured lid in the tool box of my truck and let them roll and ride around for a while until I remember to take em out. Works that same and tumbling them.

 

[Pro Libertate]

I made a wood box with a lid. I put the fresh cast balls in it and fill the bottom about half way, only one layer. Then I put that box that has a secured lid in the tool box of my truck and let them roll and ride around for a while until I remember to take em out. Works that same and tumbling them.

That’ll do! I make my own black powder, so the tumbler serves double duty. It’s also nice to be able to tumble them in the course of an hour or two versus a week.

 

[Pro Libertate]

I don’t have a lot of data, but I have weighed .595” diameter lead balls at 317 grains and .600” diameter lead balls at 325 grains. If the diameter changes the weight changes in my experience. How does tumbling change the diameter of a lead ball without changing the weight? Or does it just change the diameter a few thousands and not change the weight?

In weighing the balls this morning, I discovered variances no greater than one gram, give or take. Pretty negligible, if you ask me. Most balls measured .735 with a few at .734 or .733. Of course, one can be as fussy as they wish… it just depends on how far you want to take it.

 

[bpd303]

When I used to do all that fiddling with my cast round balls 1 gram + - difference in them would go back in the pot to be remelted. Sometimes I would separate them in equal weight lots and did notice a change in the point of impact from the lighter vs heavier lots. This was done with my most accurate 50 caliber target rifle the ugly 13th Air Force which I love.

 

[Pro Libertate]

When I used to do all that fiddling with my cast round balls 1 gram + - difference in them would go back in the pot to be remelted. Sometimes I would separate them in equal weight lots and did notice a change in the point of impact from the lighter vs heavier lots. This was done with my most accurate 50 caliber target rifle the ugly 13th Air Force which I love.

If these balls were for one of my rifles, I’d be more particular; however, given they’re .735” balls intended to be shot out of a smoothbore, I’m quite a bit more forgiving of such variances. I believe any inconsistencies in weight or dimensions from ball to ball have more to do with my inexperience in casting than any metal loss through the tumbling process.

 

[bpd303]

I had a couple of molds that left more sprue than I was willing to accept. Took the sprue plate off and used a flat whetstone to mill the mold a little until there was no more sprue protrusion.

 

[Jim in San Diego]

I had these boxes of unopened .440 Speer round balls that I purchased from a pawn shop for $10. They appeared to be oxidized, possibly from the flux that was used? I tried tumbling the balls by themselves with unsatisfactory results. It was adding just a single squirt of dry graphite that resulted in the improvement seen in the upper box. Curiously enough, rubbing the balls vigorously between my fingers doesn’t result in any residue on my fingertips or any change in their sheen.

I’ll have to try the graphite! I have a rock tumbler and successfully tumbled a bunch of 50 cal round balls, but then a batch came out severely oxidized.

I didn’t do anything different, but they were very much like your lower picture.

Then I tried to tumble larger round balls for a 75 caliber blunderbuss I’m having made. Many of the balls came out egg shaped.

Did I tumble too long? Or is tumbling not effective on the larger round balls?

 

[TFoley]

better yet, teflon tape patch!

Yup, just like Jeremiah Johnson used!!

 

[waksupi]

What your picture shows me, is your lead wasn't hot enough when you were pouring according to the wrinkles that show, and there may have been a flake of lead on the mold faces, leaving a mold line.