I only guessed about the "R" part; I don't see anything other than SAVAGE MODEL 99 (in two lines) on the front receiver bridge. The forestock looks like the one in Calhoun's pic. I've never really known how people determine model types, other than by various features? This is the only 99 I've looked at closely, and I don't see anywhere where it might say R, RS, EG, F, A, C. whatever...
But otherwise, what doesn't add up... so I can re-check?
Not drilled and tapped.
The tang sight isn't at all like the peep shown in Calhoun's pic above. I should have included info on that before; don't know what model it is, but it's marked: LYMAN MIDDLEFIELD CONN, U.S.A.
It's mounted on the tang, but extends well down the wrist of the stock where the hinge is.
The two folding leaves on the barrel have a wide V (taller) and a flat top with white triangle, apex at the top (shorter).
Given the G&H side-mount, I wouldn't be surprised if some of the other sights aren't factory. I also have a felt lined aluminum case for the Weaver scope and detachable slide-off part of the mount. Don't know if that's a G&H thing, or weather my Grandad made it (he could have), or what...
