In Kamigata, the meaning of "futatsudama" is interpreted as "futatsudama no tsuyogusuri," which means "a powerful bullet using double the amount of gunpowder," and therefore, only a single bullet is fired.
上方では、二つ玉の意味を二つ玉の強薬（つよぐすり）、すなわち「火薬が二倍使われている威力の強い玉」と解釈し、一発しか撃たない。