Zoar: You ask about 11,10, and 4 gauge round lead balls. Track of the Wolf has .735" balls that should work in the 11 gauge, which is nominals .751" in diameter. ALWAYS MEASURE THE BORE OF YOUR GUN TO DETERMINE IF ITS ACTUAL DIMENSION IS AS ADVERTISED!
A 10 gauge is nominally .775, and Track carries balls that measure .760" that should work in your 10 gauge.
The 4 gauge, or " 4-bore"( actually the term " bore " was applied to rifles of this diameter, while smoothbore guns were still measured in GAUGE.) is so uncommon that I can also find NO one who sells the balls commercially. The nominal diameter for a 4 gauge gun is 1.052", which would tend to indicate that you want a round ball that is about 1.032 or slightly small in diameter AS CAST to use in such a gun.
Considering the massive powder charges required in such a gauge, you will want to use as thick a patching material as you can get, and still use some kind of filler on top of the powder to act as a fire barrier. If you can find an appropriate sized punch, I would also suggest using a lubed wool felt wad behind the PRB to add lube to both the patch and the bore as the PRB is leaving the barrel. The felt wad would be used in addition to a filler. Corn meal is cheap, and 100 grains( by volume setting) should adequately cover the powder in such a wide diameter barrel as this.
I think obtaining round balls will be a custom mold project, and you have already been given the names of some specialty mold makers you might contact to do the job.
Since you will need to be pouring 4 oz of lead into the mold for each ball, I suggest buying the largest working lead melting pot you can get, and make sure that the hole in the sprue cutter plate is large enough to allow a lot of lead to flow into the mold quickly, before the lead in the bottom of the mold begins to cool.
The largest problem with casting such large diameter balls, is the amount of lead that has to go into the mold very quickly to keep both the lead and the mold hot enough to produce a well shaped ball. I asked a friend of mine about this. He has been a professional caster of bullets for more than 50 years, now, and when I asked about a 4 bore ball, he rolled his eyes around. He has cast 10 gauge balls, he says, but nothing bigger, and he considers the 10 gauge balls a PITA! His words.
I would not have any idea what you would legally be able to hunt with such a gun, and certainly it will have to weigh so much that its not going to be much of an off-hand target rifle for you either. Are you sure you want to go to all this expense just to have such a gun? If you get the gun operational, you might let your Chief of Police or Sheriff know you now have the right gun to shoot cars at road blocks, should he need it! :blah: :rotf:
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