Original configuration for the 7.9x57 was the 227 FBRN of 1888.
This was superceded by the 7.92mm S-bullet in 1904: 154 FB pointed, which was the standard bullet for WW1.
The JsS loading came out as a super-hot load, reserved for MG use, late in WW1. This was the 196-198 BT spitzer and it originally was intended as an anti-Tank load. Because everybody had a friend in the MG section, this ammo filtered down to the regular troopies very rapidly, being that the Tanks were scaring rhe bejabbers out of everyone they were pointed at. Everyone with any sense of survival wanted something that would knock out a Tank....... and this was pretty much IT before the TuF came along in '18.