Rifle Scope Anatomy

When selecting a Rifle Scope  it is important to know the different parts of your scope to make an informed decesion. Below is a visual guide with descriptions to each part. Be sure to also check our Guide to Selecting a Rifle Scope.
Rifle Scope Terminology
  • 1. Eye Piece
  • 2. Exit Pupil
  • 3.Ocular lense
  • 4.Power Ring
  • 5.Windage Adjustment
  • 6.Elevation Adjustment
  • 7.Objective Bell
  • 8.Eye-Bell
  • 9.Objective Lens
 
1. Eye Piece
End of the Scope you look through
 
2. Exit Pupil
The exit pupil is the size of the column of light that comes through the eye-piece of the scope. The larger that the exit pupil is, the brighter the image will be. To figure out the exit pupil size, divide the objective lens diameter by the scopes power (a 4x40 model has an exit pupil of 10mm).
 
3.Ocular Lense
The Lense on the scope that is closest to your Eye.
 
4.Power Ring
The power ring is found on scopes that have variable power, and will adjust the scopes power when turned. You will know in the scopes title if it is variable or not.  Instead of a 4x32 scope, you might see a 4 - 12 X 32 scope. In that case, the scope's magnification is variable from four to twelve power and the objective lens is 32 mm. Unless your absolutely sure of the exact power you want on your firearm, it's best to select a variable power range scope in the range you will use most.
 
5.Windage Adjustment
The windage adjustment is usually on the side turret of the scope and adjusts the scope left to right.
 
6.Elevation Adjustment
Usually found on the top turret of the scope. Elevation controls the vertical (Up-And-Down) adjustment.
 
7.Objective Bell
The objective bell is the housing that the objective lense and the tube get attached to.
 
8.Eye Bell
The housing that the eye piece and tube get attached to.
 
9.Objective lense
The Objective Lense collects the light that goes through your scope. A larger lense will let more light in and will aid in lower light conditions. Generally the higher the magnification of the scope, the larger the objective lense must be.