Description
Last update on July 5, 2022 // Source: Amazon API
Rifle Scope Product Details
Monstrum 3-9×40 AO Rifle Scope with Parallax Adjustment and Offset Scope Mount
Rifle Scope Product Features
About this item
Adjustable 3-9 times magnification, for targeting out to 500 yards and beyond
An adjustable objective lens or AO – that allows for sharper focus of the target image, elimination of parallax, and range estimation
Aircraft grade 6061 aluminum scope body with a sealed, nitrogen-charged tube for resistance to water and fog
Package includes a one-piece machined aluminum offset scope mount for mounting to Picatinny rail equipped rifles
A new line of rifle scopes for shooters that want reliable optic without the bells and whistles (or the costs that come with them). The Monstrum Tactical S3940-AO is a full-featured scope suitable for hunting, target shooting, or tactical use.
The S3940-AO weighs 1 lb 2 ounces. It has a 1 inch diameter tube and requires a mount with 1 inch diameter scope rings. The scope is 14 inches in total length. The outside diameter of the eyepiece is 44mm and the outside diameter of the objective lens is 50 mm.
The scope comes equipped with:
Adjustable 3-9 times magnification, for targeting out to 500 yards and beyond
1/4 MOA/click windage and elevation adjustment dials with locking turrets
An adjustable objective lens or AO – that allows for sharper focus of the target image, elimination of parallax, and range estimation
An aircraft grade 6061 aluminum construction, for lightweight and durable performance
A detachable throw lever for smooth and controlled adjustment of magnification dial
A sealed, nitrogen charged scope tube for resistance to fog and water
The S3940-AO includes a one-piece machined aluminum offset scope mount for mounting to Picatinny rail equipped rifles. The mount provides 2 inches of forward extension allowing for for optimum eye relief and shooting position.
3-9×32 AO Rifle Scope 2-7×32 AO Rifle Scope 3-12×42 AO Rifle Scope 3-9×40 AO Rifle Scope
Magnification: 3-9x 2-7x 3-12x 3-9x
Reticle: Illuminated Rangefinder Illuminated Rangefinder Illuminated Mil-Dot Crosshair Reticle
Scope Range: Close to Mid Range, 400+ Yards Close to Mid Range, 300+ Yards Close to Mid Range, 500+ Yards Close to Mid Range, 500+ Yards
Eye Relief: 3.5-3.8 in 3.5-3.8 in 3-3.5 in 3.5-3.8 in
Scope Rings Included: Standard Medium Profile Standard Medium Profile Offset High Profile Offset High Profile Single Piece Mount
Tube Diameter: 1 in 1 in 30 mm 1 in
Illuminated Reticle: N/A
Shock, Water, and Fog Proof:
About the Monstrum Brand
Monstrum is a premium supplier for long gun scopes, optics, mounting solutions, and other add-ons used for firearms like rifles and long guns. They design and build their products by applying materials which are resilient and long lasting. This includes the Monstrum 3-9×40 AO Rifle Scope with Parallax Adjustment and Offset Scope Mount by Monstrum. For additional shooting products, visit their website.
Information Rifle Scopes
Rifle scopes permit you to precisely aim a rifle at various targets by aligning your eye with the target at range. They accomplish this through magnification using a set of lenses inside the scope. The scope’s positioning can be adapted to take into account different ecological aspects like wind speed and elevation decreases to make up for bullet drop.
The scope’s purpose is to understand precisely where the bullet will land based upon the sight picture you are seeing with the scope as you line up the scope’s crosshair or reticle with the intended target. Most contemporary rifle scopes and optics have about eleven parts which are found within and outside of the scope. These scope parts include the rifle scope’s body, lenses, elevation turrets or dials, focus rings, and other elements. Learn about the eleven parts of glass.
Rifle Optic Types
Rifle scopes can be either “first focal plane” or “second focal plane” type of scopes. Choosing the optimal type of rifle optic is based around what type of shooting you plan to do.
Info on First Focal Plane Glass
First focal plane glass (FFP) come with the reticle in front of the magnification lens. This causes the reticle to increase in size based upon the amount of zoom being used. The outcome is that the reticle measurements are the same at the magnified distance as they are at the non magnified distance. One tick on a mil-dot reticle at one hundred yards with no “zoom” is still the identical tick at one hundred yards with 5x “zoom”. These types of scopes work for:
- Quick acquisition, far away types of shooting
- Shooting circumstances where calculations are very little
- Experienced shooters who have an idea for their target “hold over” and “lead” correlations for their long guns
- Shooters who do not mind the reticle is bigger and occupies more visual eyesight room than a SFP reticle
Second Focal Plane Scope Info
Second focal plane scopes (SFP) feature the reticle to the rear of the zoom lens. In the FFP example with the SFP scope, the 5x “zoom” 100 yard tick would be 1/5th of the non “zoom” tick.
- Long distance kinds of shooting where shooters have more time to make ballistic calculations
- Shooting where most of the shots happen within shorter spaces and ranges
- Shooters who prefer a clearer optic picture with less area used up by the bigger FFP reticle
Zoom for Glass
The quantity of zoom a scope provides is figured out by the size, density, and curvatures of the lenses inside of the rifle scope. The zoom of the scope is the “power” of the scope.
Fixed Single Power Lens Rifle Glass
A single power rifle scope will have a magnification number designator like 4×32. This suggests the magnification power of the scope is 4x power while the objective lens is 32mm. The magnification of this kind of scope can not fluctuate considering that it is fixed.
Adjustable Power Lens Optic Info
Variable power rifle scopes use enhanced power. The power adjustment is handled using the power ring part of the scope near the rear of the scope by the eye bell.
Rifle Glass Power and Ranges
Here are some suggested scope power levels and the ranges where they can be successfully used. Always remember that high power optics will not be as practical as lower powered optics since too much magnification can be a detractor. The exact same idea goes for extended ranges where the shooter needs sufficient power to see where to properly aim the rifle at the target.
Details on Glass Lens Finish
All state-of-the-art rifle optic and scope lenses are coated. Lens covering is a significant element of a rifle when buying high end rifle optics and scope equipment.
Info on Rifle Optic Lens Coatings – HD Versus ED
Some glass companies additionally use “HD” or high-def lense finishes that use different processes, polarizations, aspects, and chemicals to enhance separate color ranges and viewable target definition through the lens. This high-def finish is commonly used with more costly high density lens glass which reduces light’s capability to refract by means of the lens glass. Some scope vendors use “HD” to describe “ED” signifying extra-low dispersion glass. ED deals with how colors are represented on the chromatic spectrum and the chromatic deviance or aberration which is similarly called color distortion or fringing. Chromatic aberration can be visible over objects with well defined shapes as light hits the item from specific angles.
Single Covering Versus Multi-Coating
Various optic lenses can also have different coverings used to them. All lenses normally have at least some type of treatment or covering used to them before they are used in a rifle scope or optic.
Single layered lenses have a treatment applied to them which is usually a protective and improving multi-purpose treatment. This lens treatment can safeguard the lens from scratches while decreasing glare and other less advantageous things experienced in the shooting environment while sighting in with the scope. The quality of a single covered lens depends on the scope developer and how much money you paid for it. Both are indications of the lens quality.
Some scope manufacturers also make it a point to specify if their optic lenses are layered or “multi” coated. This suggests the lens has had several treatments applied to them. If a lens receives multiple treatments, it can show that a producer is taking multiple actions to fight various natural factors like an anti-glare finishing, a scratch resistant anti-abrasion coating, followed by a hydrophilic coating. This also doesn’t necessarily mean the multi-coated lens is better than a single covered lens. Being “much better” depends on the maker’s lens treatment techniques and the quality of materials used in developing the rifle optic.
Anti-water Rifle Glass Lens Covering
Water on a lens does not help with maintaining a clear sight picture through a scope at all. Many top of the line and high-end scope companies will coat their lenses with a hydrophilic or hydrophobic covering.
Choices for Mounting Scopes on Long Guns
Installing solutions for scopes are available in a couple of options. There are the standard scope rings which are individually mounted to the scope and one-piece mounts which cradle the scope. These various kinds of mounts also typically can be found in quick release variations which use manual levers which enable rifle shooters to quickly mount and dismount the scopes.
Hex Key Scope Ring Mounting Solutions
Normal, clamp design mounting scope rings use hex head screws to mount to the flattop design Picatinny scope installation rails on rifles. These types of scope mounts use two different rings to support the optic, and are made from 7075 T6 billet aluminum which are designed for long distance precision shooting. This type of scope install is perfect for rifles which require a long lasting, sound mounting solution which will not move no matter how much the scope is moved or abuse the rifle takes.
Quick-Release Cantilever Rifle Glass Ring Mounts
These types of quick-release rifle scope mounts can be used to rapidly attach and remove a scope from a rifle before reattaching it to a different rifle. Numerous scopes can also be swapped out if they all use a compatible style mount. These types of mounts are convenient for long guns which are transferred a lot, to swap out the optic from the rifle for protecting the scope, or for scopes which are used in between numerous rifles or are situationally focused.
Optic Tube Sealing and Gas Purging
Moisture inside your rifle scope can mess up a day of shooting and your pricey optic by causing fogging and creating residue inside of the scope tube. Many scopes prevent wetness from getting in the scope tube with a system of sealing O-rings which are waterproof.
Rifle Glass Gas Purging
Another part of preventing the accumulation of moisture inside of the rifle optic’s tube is filling the tube with a gas like nitrogen. Considering that this space is already occupied by the gas, the glass is less altered by temperature changes and pressure variations from the external environment which might potentially allow water vapor to seep in around the seals to fill the void which would otherwise exist. These are good qualities of a decent rifle scope to look for.
