NRA NRA Sight Systems & Optics 1 — Questions and Answers
Question 1: What term describes the proper relationship between the front sight post and the rear sight notch when they are correctly aligned for aiming?
- Sight picture
- Sight alignment (Correct answer)
- Sight radius
- Point of aim
Correct answer: Sight alignment
Sight alignment refers to the correct positioning of the front sight within the rear sight notch, which is a prerequisite for accurate shooting.
Question 2: Which type of iron sight uses a circular rear aperture through which the shooter looks to align with the front sight?
- Open sight
- Express sight
- Peep (aperture) sight (Correct answer)
- Buckhorn sight
Correct answer: Peep (aperture) sight
A peep or aperture sight uses a circular hole as the rear sight element; the eye naturally centers the front sight in the aperture for consistent alignment.
Question 3: What is 'sight radius' on a firearm?
- The field of view provided by an optical scope
- The adjustment range of a fully adjustable rear sight
- The distance between the front and rear sights (Correct answer)
- The diameter of a rear aperture sight
Correct answer: The distance between the front and rear sights
Sight radius is the measured distance between the front and rear sights; a longer radius reduces angular aiming error and generally improves practical accuracy.
Question 4: Which sight technology gathers and concentrates ambient light through an optical polymer rod to produce a bright aiming dot?
- Tritium night sight
- Ghost ring sight
- Holographic sight
- Fiber optic sight (Correct answer)
Correct answer: Fiber optic sight
Fiber optic sights use a polymer optical fiber to collect surrounding light and concentrate it at the tip, creating a bright, high-visibility aiming point in daylight conditions.
Question 5: In the context of firearm sights and ballistics, what does the abbreviation 'MOA' stand for?
- Maximum Optical Aperture
- Muzzle Offset Allowance
- Minute of Angle (Correct answer)
- Mechanical Output Adjustment
Correct answer: Minute of Angle
MOA stands for Minute of Angle, an angular unit approximately equal to 1.047 inches at 100 yards, universally used to express sight adjustments and group sizes.
Question 6: Which self-luminous sight type uses sealed vials of tritium gas to provide illumination in low-light and no-light conditions without batteries?
- Photoluminescent sight
- Fiber optic sight
- Laser sight
- Tritium night sight (Correct answer)
Correct answer: Tritium night sight
Tritium night sights contain small borosilicate glass vials filled with tritium gas, which emits light through radioluminescence and requires no external power source.
Question 7: A 'ghost ring' rear sight is best described as which of the following?
- A holographic reticle projected onto a lens
- A large-diameter, thin-walled rear aperture that visually fades during focus (Correct answer)
- A see-through scope mount with iron sight backup
- A disappearing-style front sight used on double-action revolvers
Correct answer: A large-diameter, thin-walled rear aperture that visually fades during focus
A ghost ring sight features an oversized, very thin rear aperture; because the ring is thin and large, the shooter's eye naturally ignores it (it 'ghosts') while focusing on the front sight and target, enabling fast acquisition.
NRA NRA Sight Systems & Optics 1
What term describes the proper relationship between the front sight post and the rear sight notch when they are correctly aligned for aiming?