
Diamondback 3-9x40
Dead-Hold BDC Reticle | 1 Inch Tube


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Diamondback® 3-9x40 Riflescope
The Diamondback® — loaded with features! First, the solid one-piece aircraft-grade aluminum alloy construction makes the Diamondback® riflescope virtually indestructible and highly resistant to magnum recoil. Argon purging puts waterproof and fogproof performance on the agenda, and advanced fully multi-coated optics raise an eyebrow when crystal clear, tack-sharp images appear in the crosshairs. Look for all this and more in a riflescope you'd expect to cost quite a bit more-but doesn't. We can live with that.
- 3-9x40 riflescope is ideal for big game, muzzleloader, and slug shotgun applications.
- Dead-Hold BDC reticle has a customized design that helps eliminate guesswork on hold-over and windage corrections. Good for any hunting or shooting at varying ranges where estimating hold-over would be a concern.



Magnification | 3-9 x |
Objective Lens Diameter | 40 mm |
Eye Relief | 3.3 inches |
Field of View | 44.6-14.8 feet/100 yards |
Tube Size | 1 inch |
Turret Style | Capped |
Adjustment Graduation | 1/4 MOA |
Travel per Rotation | 15 MOA |
Max Elevation Adjustment | 70 MOA |
Max Windage Adjustment | 70 MOA |
Parallax Setting | 100 yards |
Length | 11.7 inches |
Weight | 14.4 ounces |
Product Manual (PDF) | Download |
Product Manual 2 (PDF) | Download |
Optical Features | |
Fully Multi-Coated | Increases 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. |
Construction Features | |
Tube Size | 1-inch 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. |
Precision-Glide Erector System | Uses premium components in the zoom lens mechanism to ensure smooth magnification changes under the harshest conditions. |
Capped Reset Turrets | Allow re-indexing of the turret to zero after sighting in the riflescope. Caps provide external protection for turret. |
Internal Mechanism Design Features | |
Precision-Glide Erector System | Uses premium components in the zoom lens mechanism to ensure smooth magnification changes under the harshest conditions. |
Convenience Features | |
Fast Focus Eyepiece | Allows quick and easy reticle focusing. |
Magnification | 3-9 x |
Objective Lens Diameter | 40 mm |
Eye Relief | 3.3 inches |
Field of View | 44.6-14.8 feet/100 yards |
Tube Size | 1 inch |
Turret Style | Capped |
Adjustment Graduation | 1/4 MOA |
Travel per Rotation | 15 MOA |
Max Elevation Adjustment | 70 MOA |
Max Windage Adjustment | 70 MOA |
Parallax Setting | 100 yards |
Length | 11.7 inches |
Weight | 14.4 ounces |
Product Manual (PDF) | Download |
Product Manual 2 (PDF) | Download |
Diamondback 3-9x40 Dimensions

Lengths | |||||
L1 | L2 | L3 | L4 | L5 | L6 |
11.7 | 2.0 | 2.1 | 5.4 | 3.0 | 3.1 |
Heights | |
H1 | H2 |
1.89 | 1.69 |
Dimensions measured in inches.

Dead-Hold BDC Reticle
Customized dot design helps eliminate guesswork on holdover and windage corrections. Good for hunting/shooting at varying ranges where estimating holdover is a concern.
Subtension detail for the Diamondback 3-9x40 Dead-Hold BDC Reticle. >
Read the Dead-Hold BDC Reticle manual for details on using the reticle for bullet drop compensation and wind drift compensation and ranging.
What’s primary difference between Crossfire II and Diamondback 3-9x40 scopes? There’s a gap. Precision glide erector system? Also, is one better for slug guns and why? Thanks!!
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