CZ 457 benchrest scope setup question

[johnrose]

Newbie benchrest shooter, so totally clueless here. I've been going to informal matches once a month as the weirdo using a Henry Golden Boy (and having fun) but am looking to now purchase a more realistic firearm for benchrest shooting, and have settled on the CZ 457 Varmint MTR.

I am seeing a lot of mentions about using the 419 rail for mounting a scope. Why do you need the additional rail if the receiver already has the 11mm dovetails? Additional points for explaining what the 15/30/50 MOA differences are, I'm not understanding what the difference is between them. Mainly shooting at 50 yards, with occasional pushing out to 100 yards.

slope game​

Thanks!

 

[linekin]

The reason for the different moa rails is additional elevation for extended yardages. That, & some like to have the erector tube more centered in the scope.
Also probably thought as more robust that the factory dovetails + many already have a stash of rings on hand.
For your intentions the factory dovetails should be fine.

 

[glp]

If you are shooting primarily at 50 yards, or even 100 yds, you don't need a rail where the rear is higher than the front.