When I see an external hammer that has to be cocked manually I call it a hammer gun. How is it semi-hammerless? Not picking a fight, just trying to understand. SRH
Winchester used the term Semi-Hammerless because it does not have a hammer striking a firing pin. What looks like a hammer is a cocking piece for a coil spring loaded striker. It is thus hammerless in the sense it is striker fired, but it has to be hand cocked with the Hammer looking cocking piece. Hammerless & self cocking are not necessarily one & the same. Lefever called his first gun with internal hammers, hammerless, even though those hammers had to be hand cocked by a long side lever. The vast majority of guns we refer to as hammerless actualy just have self-cocking internal hammers.
The Stevens model 315 with its strikers was a rue hammerless gun which was also self cocking, A double though, not a single.