I shoot a lot of cast bullets ranging from .22 cal fiber to .375 H&H. Getting decent .22 cast bullets is a royal PITA. The only alloy that gave decent casts was with pure linotype and even then the reject rate was quite high. Sometimes, over 50 percent ended back up in the pot. The very slightest flaw was reason for rejection and the slightest difference in weight was enough to reject. My loads FWIW was more in the range of a hot .22 WRF.
What I would consider regarding your specs would be the round ball as mentioned of a gallery load for the 30-30. Feeding would not be a problem in your single shot and something in the 100 to 120 gr. range with a light load of Unique. I use 5.0 gr. on my M94 Winchester but at that level is still supersonic. Feeding in lever actions is fussy at best with the lighter bullets borderline in a Marlin and no go in the M94, The 100 to 115 gr. bullets won't deed in the 94 but are borderline in the Marlin. The 120 gr. bullets will feed in the M94 if seated as far out as practical. At least they do in my rifle. None of that is a problem in a single loader. Gallery loads in a 30-30 or any .30 caliber rifle are a lot of fun as plinkers and with a bit of tweaking for your particular rifle make great small game loads.
Paul B.

Our forefathers did not politely protest the British.They did not vote them out of office, nor did they impeach the king,march on the capitol or ask permission for their rights. ----------------They just shot them.
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