Dave, actually the Vetterli is a bolt action repeater. It uses 10.4 X 38R rimfire ammo (. 41 Swiss). Many of these surplus rifles were imported, cut down, and offered as inexpensive hunting rifles in the early 1900s. Ammo was commercially available back then but hasn't been made for several decades. I have modified some bolts to center fire for myself and others. Brass making is a time consuming job, but satisfying. This is usually done using 348 Win. or 8mm Lebel brass.