I have two Smith's with the "R" suffix. Both the same except ga. and barrel length. One 20ga. 26' barrels and one 12ga. 28" barrels. Both have curtis forends, both double triggers, both three position safety, both extractors, both fw's acording to side plates. 20ga. 1915, 12ga. 1916. Mr. Stubbendieck i will be glad to give you the serial numbers if that would help. Hope this helps.