AFAIK, the Colt PPS (the "S" stands for "Special") never was chambered so it would accept .357, but the first (prior to c. 1903) New Army and Navy revolvers (and military equivalents) were. The .357 Magnum did not exist when those guns were first made and the chambers were bored straight through, with the barrels drilled .380" for the old Colt .38. When Colt cut the chambers with the proper shoulders and rifled the barrels for a .357 bullet, marksmanship improved radically.
Jim