Hi Wheeler!
I've been molding Minnie balls the last few evenings . I have two molds I use , an Aluminum Rapine mold and a steel RCBS Hodgdon.
Of the two the Hodgdon is easier once it gets hot.I literally took me some time (several seasons in fact ) to figure out what works .
All my early bullets looked just like you described .The first bullets out of my molds still look like that.
1)Hot lead is critical .Really hot .On my old pot I crank it all the way to 800(That's an ''11'' on your guitar amps
) .
It has to run freely out of the lee dipper I use. Your thermostat might work better than mine .
Some pots work better at a certain lead level .Mine casts better bullet from about 3/5th down to about 1/5th .I suspect the pot heats the lead best at those levels.
2) Graphite mold release definitely works.(I understand Mr Rapine has retired but I might be wrong)
3) When pouring lead into the mold ,the mold should be tilted to slightly to one side .The position and angle of the mold and the ladle's lead stream and its entry angle make a difference ,check as you go along and pay attention to what you are doing .Repeat what works .
4) When the stream of lead goes into the mold there should be enough of an opening left to let air escape
5) Keep pouring lead even if it is just a small stream on the opening after it is full .It helps prevent cooling'' sink holes'' on the nose
6) Flux your lead often .I use candle wax (paraffin ) I use my covered lee dipper by filling a bit of the cavity with a bunch of candle shavings then (gently) plunge the whole thing to the bottom of the mold and start stirring it in.
Once infused step back it will start smoking .
Hopefully you are doing this outside .These are fumes you don't want to be breathing. Wearing thick leather gloves with some polycarb lensed safely glasses .After it is done smoking take an old spoon and push to one side then scoop of the dusty crud exposing nice fresh clean lead .
I scoop lead from the very bottom on the theory that the purest and possibly the hottest lead lurks in the bottom of the pot.
Molding is a learned skill ,Minnie balls are just about the hardest kind of bullet to mold .The Lee's thin skirt make them trickier.
Now Daryl is correct in his criticsism of the Minnie Ball. Everything he said was true .Round balls are flatter shooting and good for hunting .
They are very flexible in regards to different powder charges , are accurate. With a big enough bore and a hardened bullet they were effective even as elephant killers.
The Rifle musket was not designed for hunting , it does load a lot faster and if you account for the trajectory it is very accurate.
Minnie rifles are a system ,built for uniformity, simplicity of use,and for launching a specific balanced load for a certain range for 19th century military use .
That is why for modern use they make durable, easy to maintain, deer rifles for moderate ranges and are good target guns
The top caps it uses make them very reliable. If you have an old one the parts still interchange after 150 years !
I am very fond of mine of my 3-band .