This is Brown Bess Musket in Gunbucket format. Gunbucket is 240pix = 1ft Gunbucket is a sub-branch of Shipbucket
Brown Bess Musket is the main battle weapon of the British Empire from 1722-1838, Brown Bess is a nickname of uncertain origin for the British Army's muzzle-loading smoothbore Land Pattern Musket and its derivatives. This musket was used in the era of the expansion of the British Empire and acquired symbolic importance at least as significant as its physical importance. It was in use for over a hundred years with many incremental changes in its design.
Concept art for Awesome Man. More on that here: [link]
When I first got the assignment I went home and did a concept of what I thought the character could look like. Though it set the illustrative tone for the book, ultimately, design was the wrong direction for the character. But I still really like it.