Second Focal Plane Reticles
Second focal plane (SFP) reticles are located near the scope’s eyepiece behind the image erecting and magnifying lenses. This style of reticle does not visually change in size when you change the magnification. The advantage of an SFP reticle is that it always maintains the same appearance.
For PST models using second focal plane reticles the listed reticle subtensions used for estimating range, holdover, and wind drift correction are only correct at the highest magnification.
The Subtension Scale: MOA
A minute of angle will subtend 1.05 inches at a distance of 100 yards. Viper PST riflescopes with MOA adjustments use 1⁄4 minute clicks which subtend .26 inches at 100 yards / 7.3 mm at 100 meters, .52 inches at 200 yards / 14.6 mm at 200 meters, .78 inches at 300 yards / 21.8 at 300 meters, etc.
Windage and Elevation Adjustments
Vortex Viper PST riflescopes incorporate precision finger adjustable elevation and windage dials with audible clicks.
To make adjustments:
1. Turn the adjustment knob in the appropriate direction: Up/Down or Left/Right as indicated by the arrows.
2. Following the directional arrows, turn the knobs in the direction you wish the bullet’s point-of-impact to go to.
With each click of the Viper PST moving the point-of-impact 1/4 MOA, four clicks of the knob will move a bullet’s point-of-impact 1.05 inches at a 100 yard sight-in distance. At 100 meters, four clicks will more the point of impact 29.1 mm.
RZR Zero Stop
Vortex Viper PST riflescopes incorporate the RZR Zero Stop feature. After the rifle is sighted in, the RZR Zero Stop allows fast, sure return to the original zero point when large multi-revolution elevation corrections have been dialed into the riflescope.
Without a zero stop, the shooter must pay very careful attention when dialing large corrections needing multiple revolutions of the elevation knob. If the shooter loses track of the number of revolutions, the original zero point may become lost. Because of the RZR Zero Stop, the elevation knob on Vortex Viper PST scopes can be quickly spun back to the original zero without having to carefully count revolutions.
Once the RZR Zero Stop is set, the elevation knob will stop turning at the original zero point when being returned from a temporary elevation correction.
|XD™ Lens Elements||Extra-low dispersion (XD) glass increases resolution and color fidelity, resulting in crisp, sharp images.|
|XR™ Fully Multi-Coated||Proprietary coatings increase light transmission with multiple anti-reflective coatings on all air-to-glass surfaces.|
|Second Focal Plane Reticle||Scale of reticle maintains the same ideally-sized appearance. Listed reticle subtensions used for estimating range, holdover and wind drift correction are accurate at the highest magnification.|
|Glass-etched Reticle||Protected between two layers of glass for optimum durability and reliability.|
|Illuminated Reticle||Provides precise aiming under low-light conditions.|
|Tube Size||30 mm diameter.|
|Single-Piece Tube||Maximizes alignment for improved accuracy and optimum visual performance, as well as ensures strength and waterproofness.|
|Aircraft-Grade Aluminum||Constructed from a solid block of aircraft-grade aluminum for strength and rigidity.|
|Waterproof||O-ring seals prevent moisture, dust and debris from penetrating the riflescope for reliable performance in all environments.|
|Fogproof||Argon gas purging prevents internal fogging over a wide range of temperatures.|
|Shockproof||Rugged construction withstands recoil and impact.|
|Hard Anodized Finish||Highly durable low-glare matte finish helps camouflage the shooter’s position.|
|ArmorTek||Ultra-hard, scratch-resistant coating protects exterior lenses from scratches, oil and dirt.|
|Tactical-Style Turrets||Exposed turrets provide fast, accurate and easily read elevation and windage adjustments.|
INTERNAL MECHANISM DESIGN FEATURES
|RZR Zero Stop||Zero Stop mechanism prevents the turret from dialing below sight-in range.|
|Precision-Force Spring System||Uses premium components in the erector-spring system to ensure maximum repeatability and ease of adjustment.|
|Precision-Glide Erector System||Uses premium components in the zoom lens mechanism to ensure smooth magnification changes under the harshest conditions.|
|Radius Bar||Fiber optic turret rotation indicator provides a highly visible and tactile point of reference for turret rotations. US Patent 7,937,879|
|Fast Focus Eyepiece||Allows quick and easy reticle focusing.|
|Built-In Accuracy Features||Matching (MRAD or MOA) turrets and reticles facilitate fast and accurate shooting at extended ranges. The patented fiber optic Radius Bar visually assists tracking turret rotations. US Patent 7,937,879|
|Objective Lens Diameter||44 mm|
|Eye Relief||3.4 in|
|Field of View||41.2-8.6 feet/100 yards|
|Tube Size||30 mm|
RZR Zero Stop
|Adjustment Graduation||1/4 MOA|
|Travel per Rotation||25 MOA|
|Max Elevation Adjustment||75 MOA|
|Max Windage Adjustment||40 MOA|
|Parallax Setting||20 yards to Infinity|