I'm by no means an expert, but I think the 48 was mostly for round sided actions....Win 54, 70, Springfield '03, Mauser, etc.. From what I know the 56W71 was the Lyman receiver sight for the Model 71. Might be a model stamp on the sight & pictures would help.
*A Lyman 66A will fit a Model 71 also but came along toward the end of M71 production. If you're just comparing adjustment knobs, both coin slotted and knurled were available.
Last edited by tmitch; 10/25/16.
