"760" marked on any silver means that the object contains 76% silver (and 24% other metals).
750 means 18kt the stamp might be a little damaged to look like 760.
The Roman numeral of DCCLX is equivalent to 760
It means a distance of 760 miles is traveled every hour.
I have not seen a 760 marked 760R, but they are stamped Carbine. What is the barrel length? Can you post some pictures? If it is a cut off rifle, as I suspect, then the value is only as a shooter. If you mean the R that has a circle around it after the 760 on the receiver, that is to indicate that 760 is a Remington trademark. There is no record of a 300 Sav. being made in the carbine length, only; 30-06, 270, 280, 308, and 35 Rem.
760
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It is 760 when rounded to the nearest ten.
The nearest 10 of 762 is 760.
35% of 760= 35% * 760= 0.35 * 760= 266
51% of 760 = 51% * 760 = 0.51 * 760 = 387.6
760