View Full Version : Having perfect balls

Ohio Rusty
02-10-2007, 02:01 PM
Yes .... you casters can all have perfect balls too. And having them made from pure lead is even better !! The credit to the following casting technique goes to two fellows that call themselves the 'Bevel Brothers' who write for Muzzleblasts, the NMLRA magazine for blackpowder shooters. A few years ago, they shared some information on casting without voids, and I wanted to share that info with the list for those who haven't seen or read the info. I tried the technique and I was amazed to cast ball without voids and bubbles, as when I cut the ball in half, they were solid inside without bubbles ..... *NOTE*: This technique only works with a hand pour method, and will not work with a bottom pour pot, unless you use the pot with a ladle and hand pour the ball. OK ..... What happens when lead is poured into a round ball mould is the molten lead cools first around the sprue hole, then the body of the ball hardens. That is why when you pour lead in the mould and you have that little puddle on top, you can actually watch a dimple form on top of the puddle as it cools. That dimple is actually the lead being pulled down into the void inside the ball, as the sprue puddle is hardening and the ball below is still molten. Since the sprue hole cools first, and hardens first, the air trapped inside the mould has no place to escape to. Yes, there are air escape lines cut into moulds, but they don't always let all the air out that is trapped inside the mould itself. Consequently, as the puddle over the sprue hole cools, the bubble or void that is trapped in the ball stays there as the ball lead hardens around the bubble. These ball that have a void don't always fly straight as the weight of the ball isn't equal around the spinning axis as it flies downrange. It's much like the joke golf balls you can buy that are heavier on one side, and when you putt them, they wiggle and won't roll straight. The same happens with a lead ball that is heavier on one side. The ball spins unequally on it's axis, and the resulting shot is off the mark or acts like a flyer. So how do you pour lead and not get voids and bubbles ??? The secret is making the sprue hole cool last, permitting any air trapped down into the ball itself escape thru the sprue hole as the body of the lead ball hardens. You keep your mould over the lead pot, and angle it downward slightly to let all the excess lead run back into the pot. You fill your ladle and pour the ball, but DON'T STOP POURING !!! Keep pouring and pouring the molten lead into the sprue hole, letting the excess molten lead run over the mold and back into the pot below. Pour until your ladle is empty. What has now happened is the sprue hole remained molten while the ball hardened below the hole, letting excess air escape thru the molten lead, thru the sprue hole. Don't worry about any excess lead on top or over the mold when done pouring, as that easily comes off when the sprue cutter plate is struck to shear the sprue from the ball in the mould. When I tried this method of casting round ball, I was amazed that not one of my new poured ball had any voids or bubbles when I cut them in half to check. My older bottom pour ball had bubbles, some of them big bubbles, in 50% of the poured ball. Those all went back into the pot to be re-cast. Consequently, I ended up changing my bottom pour pot into a ladle/hand pour pot only. I did want to add that I'm not condoning anyone to completely change their casting ways, as many on here have been casting perfectly for years without problems. I just wanted to include the above pouring info so casters on the list can add another piece of information to their casting knowledge when it comes to making perfect muzzleloading boollits. I also don't know if bottom pour-type pots leaves bubbles in smokeless powder boolits, or if a bubble even has any effect on a smokeless type boolit due to its high velocity and extremely fast spin compared to the slow spin of a muzzleloading barrel (one turn in 66 inches or slower). I hope I have passed along some info that casters and front-stuffer types on the list will find useful. Give this 'flooding the mould' method a try the next time you set down to cast round ball and pass along your results.
Ohio Rusty

"Happiness is a warm ingot".

02-10-2007, 02:12 PM
Right on, Rusty. Good job in writing that up. To get extra air into that mold and still use the pot as normal without ladle, sand the parting line of the mold halves very slightly where the sprue plate goes across. This creates an avenue for air to excape under the sprue plate itself. ... felix

02-10-2007, 06:21 PM
I get the same results by keeping the ladle tight to the sprue hole for a longer time then most casters do. This keeps the sprue molten until the mold is full. You will see the lead in the ladle go down at the start, stop and then go down again. Only then do I tip off the ladle. You are right that the sprue can't be allowed to harden first and my way works as good as slopping lead all over. Just filling a mold fast and letting the boolit suck in lead from the sprue does not work and is the reason why I don't like to pour from the bottom or from a distance above the mold. You have to feed the boolit molten lead until it can't take any more.
I get as close to zero rejects as is possible.
I think my boolits harden from the bottom up!

02-10-2007, 09:42 PM
I sorta came apon this my self some years ago in casting minnes.Cocking the mould and pouring till full then rotating the blocks allmost level while still pouring.
With one mould I have a [RCBS Hodgen] the hardest mould I have to fill. I would throw back 30-50%.After going like above I have cut down the rejects to less than 5%.
Only drawback is amount of lead oxide created on top of the melt by letting this metal fall back into the pot..You got to skim a LOT. But I just reclaim it later in the smelter by adding sawdust [or whatever you use] for flux. You get back allmost all oxide as clean metal. It is more work but I just hate cast bad boolets just to throw them back.

02-27-2007, 05:41 PM
I pre heat my mold. My first is perfect. I just spent two days casting for a friend and have a huge pile without one single reject. I usually figure at least one bad one per 100 but I have not had to put any back in the pot for this batch.
Try my way once. Just keep the ladle tight to the plate for a longer time to keep the sprue molten. Larger boolits need more time then small ones. Just let the mold fill until it can't take more lead. The dimple on top of the sprue when it cools should be very small. You do not want the boolit to pull lead from the sprue, because it can't.
I spent years weighing boolits and found it is a waste of time when cast right.

50 Caliber
04-25-2007, 08:49 PM
I use Lee 495" ball mold and I heat it up on Hot plate while waiting for the lead to come up to temp in my furnace. My balls are frosty sometimes, but well filled out and I dont have to throw many back.