The only way I know of for sure, is the tang stamp saying Schrade, or Schrade Walden.
The 8 Old Timer Stockman was previously named the 881, but later Schrades, like my yellow ones, were also labeled 881.
The jigged delrin was mostly used by SW, and then, when the Old Timer name came along, the sawcut delrin was mostly used.
Then, I don’t think the pull gives a definitive clue either. Although I guess I’ve seen the long pull, and the matchstrike long pull on SW more often, vs the nail nick on Schrades.
Another small difference, but not always, is the model number being on the back of the tang on the Schrade Waldens.
The one I toted yesterday has Schrade Walden on the mark side of the tang, and 8OT on the pile side of the tang. It has the matchstrike long pull, and sawcut delrin. I think all those clues probably mean it was from just before they changed from Schrade Walden to just Schrade.
Here’s another that I have on me now, a Schrade Walden 879. Probably a bit older, with the jigged delrin. This one has rounded bolsters, and more of a curve to the frame, but it’s the same size as the 881/80…
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