44 Henry spherical. Henry also supervised a whole new rifle style centered loosely within the Volcanic to use The brand new ammunition, retaining only the final sort of the breech system and the tubular journal. This became the Henry rifle of 1860, which was made by the New Haven Arms https://highimpactrounds.com/product/winchester-super-x-22-lr-round-nose-40-gr-1300-fps-100-rd-box/