Think RT preceded the RP. In the "old days", we always called this a "Round Top"-------No big deal. The mounts for scope application were the same as those for the Remington 700.
Just for comparison....Both M77s manufactured in 1972. 2000 SNs apart..and judging from the way the 5s & 7s are hand written, I'd say the same person did the numbering on both boxes.
This is of my M77ST, with sights and round top.
This is of the M77R.T, with sights and round top on GunBroker.
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