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The R/T reticle is based on a form of angular measurement
called the milliradian (mrad for short). These angular
measurements allow a user to calculate ranges when
comparing the
reticle to objects
of known
dimension. The
key to effective
ranging using
this reticle
is knowing
common objects
in your vicinity
and their
measurements.
The Viper R/T reticle also uses a secondary system of quick
ranging based on a human silhouette.
See the section on Quick
Ranging with Silhouettes.
1 mrad subtension marks
.5 mrad subtension marks
.5 mrads
1 mrad
Fine crosshairs
subtend .05 mrads
Heavy crosshairs
subtend .5 mrads
Reading the R/T Reticle
Using the Viper R/T Reticle
All silhouette dimensions are accurate at the listed ranges.
28cm / 11”
50cm / 20”
35cm / 14”
44cm / 17”
79cm / 31”