44 Henry round. Henry also supervised a whole new rifle structure centered loosely on the Volcanic to make use of the new ammunition, retaining only the overall type of the breech mechanism along with the tubular magazine. This grew to become the Henry rifle of 1860, which was made by https://highimpactrounds.com/product/winchester-super-x-20-ga-2-75in-20-pellets-3-buck-1200-fps-5-rd-box/