As to rifle ctg. size and repeated shots, a .45 3 1/4 loaded with 115gr. 2F in RCBS cases and 122gr. in Bell brass qualifies. In both of these I was using an undersized 460 and 500gr. Smooth slug that after patching was .4505" to .451" in diameter. A 5/16" thick grease cookie of 40% Vaseline, 60% Beeswax allowed 10 consecutive shots without wiping. A dry patch removed all traces of fouling after 10 shots. I do not know how many could be fired without losing accuracy as I only fired 10 in a row, then wiped.
I was unable to find bee brood foundation, so used a disk of wax paper between the powder and a .035" wad of tablet backing or beer case box card stock under the bullet. Powder was compressed 110" before inserting the wax paper disk thin wad and bullet. The bullets were a weak friction hfit in the case with only 1/4" of it in the case.
Tony, your experience in this is quite as vital as any other's.