20-MOA Scope Mount?

[alamo308]

A newbie wants to know:
So, for example, a recommended 'starter' come-up from 100-yard zero to 1000 yards being 38 MOA, would the 20-MOA scope mount reduce that come-up to 18 MOA?
Or... does the 20-MOA mount merely ensure that the scope will have the adjustment range to make the ~38 MOA come-up?
???

 

[Turbulent Turtle]

A newbie wants to know:
So, for example, a recommended 'starter' come-up from 100-yard zero to 1000 yards being 38 MOA, would the 20-MOA scope mount reduce that come-up to 18 MOA?
Or... does the 20-MOA mount merely ensure that the scope will have the adjustment range to make the ~38 MOA come-up?
???

In a word, yes.

In more words, what a 20MOA ramp does is to make the scope aim a third of a degree lower at mechanical zero (provided everything else is exact) so as to provide an extra 20MOA of up elevation and thus be able to have a zero at longer distances.

Consider a scope with a total of 50 MOA of elevation adjustment. If everything was perfect with the scope mound and base and so on, the scope would be aligned with the barrel when it was set at mechanical zero with 25 MOA of available down adjustment and 25 MOA of up elevation. Continuing in our perfect world, suing the 20MOA ramp on this setup would then have the scope aligned (parallel) to the barrel with 5 MOA of down elevation and 45 MOA of up elevation.

Without leaving our perfect world, your rifle would be on target at 100 yards with about 8MOA of down and 42 MOA of up elevation. If you needed 38 MOA to zero at 1000 yards, that zero would leave you with about 46MOA of down elevation and 4 MOA of up.