1. Gather all the required information. You will need the following information about your March Scope and your rifle to use the calculator:
2. Enter the above information in the corresponding fields of the calculator
3. In the RING HEIGHT field of the calculator choose different options for ring heights until you get, in the RESULTS section, the clearance that you want between the bottom of the objective scope cover and the barrel.
March 30 mm rings are available in a height of: 26, 30, 34 and 37mm.
March 34 mm rings are available in a height of: 30, 34 and 37mm.
Objective Lens - Scope's Outside
Diameter Diameter .
24 mm - 33 mm
42 mm - 51 mm
52 mm - 60 mm
56 mm - 64 mm
DEON points out a few exceptions to be aware of that the ring calculator above does not consider in it's calculation.
When the OD diameter of the objective lens is smaller than the OD of the eye piece the zoom ring may hit the rail.
Also as in the above picture, this is a case where the rear sight may hit the eyepiece.
PROTOTYPE PICTURE ONLY!