[Were the No 3s factory drilled and tapped for scope bases?]
Not all were so factory prepped. 8)
When first introduced, the #3 wasn't factory D/T'd for the two Weaver-type short bases - but that soon changed.
I can't recall exactly when, nor which chamberings were invovled, at this late date - but methinks it might have ben only the first chambering (.45-70) involved, with the other startup chamberings introduced after the change to scope prep.
Just a WAG, but Weaver most likely immediately jumped on the fact when the #3 was introduced, and made bases with the caveat - but never updated their caveat because there are sure to be some pre-update specimens still out there.
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