Complex sentence: Model 1887 production totaled 64,855 units between 1887 and 1901, with an additional 14,600 Model 1901 shotguns being manufactured before the product line was discontinued in 1920.
Split into simpler sentences: Model 1887 production totaled 64,855 units between 1887 and 1901. An additional 14,600 Model 1901 shotguns were manufactured before the product line was discontinued in 1920.