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You are here: Home / Rifle Scopes / Monstrum 1-4×20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 1 Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 2 Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 3 Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 4 Monstrum 3-9x32 AO Rifle Scope with Illuminated Range Finder Reticle and Parallax Adjustment | Monstrum Flip Up Scope Cover Set | Bundle
Monstrum Rifle Scope 5 Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 6 Monstrum 1-3x20 Rifle Scope with Rangefinder Reticle | ZR255 H-Series Offset Scope Mount | Bundle
Monstrum Rifle Scope 7 Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle

Monstrum 1-4×20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle

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SKU: ee7798cd4c34 Category: Rifle Scopes Tag: rifle scope
  • Description
  • Additional information

Description

Rifle Scope Product Details

Monstrum 1-4×20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle

Rifle Scope Product Features

About this item
Tactical rifle scope providing crystal clear targeting at 1-4x magnification, with a 20mm objective diameter and an eye relief of 3.5-3.8 Inches
Glass rangefinder reticle for on-the-fly range estimation and long distance targeting
Lever controlled reticle illumination in both red and green with multiple brightness intensities
Aircraft grade aluminum construction with a 1 inch sealed, nitrogen charged tube for resistance to water and fog
Product Bundle includes Monstrum H-Series One Piece Offset Scope Mount; comparable in weight to a pair of scope rings while maintaining the added rigidity and convenience of a one piece mount; Includes hardened steel Torx mounting hardware for mounting to any Picatinny rail platform.
The Monstrum Tactical S1420-R-RG is a reliable tactical scope great for close to mid-range shooting. Crystal clear optics with 1-4x magnification. Rangefinder reticle for faster range estimation and holdover correction. All Monstrum scopes tubes are nitrogen filled for resistance to water and fog.
This scope has 1/2 MOA/click windage/elevation adjustments with the ability to lock the turrets and reset the zero.
The etched black reticle is always visible without illumination or can be lit red or green for better reticle visibility at night or low light environments.
With the built-in throw lever, moving the magnification ring can be done with ease for quick yardage adjustments.
Multi-layer lens coating, protects your scope lens from scratches, and fog, while improving the clarity of your vision.
Includes: 1-4×20 Rifle Scope, Standard Medium Profile (Black Scope), Detachable Throw Lever, CR1632A Battery, Lens Cloth, Lens Cover
Reticle: Illuminated Rangefinder
Materials: 6061 Aircraft Grade Aluminum
Compatibility: Rifles with Picatinny Rails
Scope Range: Mid-Range, Up to 500 Yards.
Magnification: 1-4x
Objective Diameter: 20 mm
Tube Size: 1 in
Eye Relief: 3.5-3.8 in
Weight: 11 oz
High Quality Construction
Crafted from aircraft grade aluminum, the scope is both sturdy and lightweight, with a 1 in sealed tube. The scope is 8.5″ in length, 2.0″ in width, 1.8″ in height and 11 oz in weight. It comes with lens covers and one 3V CR1632 battery.
Reticle: Illuminated Range Finder Illuminated Range Finder
6061 Aircraft Grade Aluminum
Compatible with Picatinny Style Rifles
Scope Range: Mid-Range, Up to 500 Yards. Mid-Range, Up to 500 Yards.
Magnification: 1-4x 1-4x
Objective Diameter: 20mm 20mm
Tube Size: 1 in 1 in
Eye Relief: 3.5-3.8 in 3.5-3.8 in
Scope Rings: Standard Offset
Flip Up Lens Covers:

About the Monstrum Scope Maker

Monstrum is a premium maker for long gun scopes, optics, mounts, and other add-ons used for guns like rifles and long guns. They innovate and supply their mounts, scopes, and related products making the most of building materials which are resilient and long lasting. This includes the Monstrum 1-4×20 Rifle Scope with Rangefinder Reticle | ZR250 H-Series Offset Scope Mount | Bundle by Monstrum. For additional shooting items, visit their site.

What You Need to Know About Rifle Optics

Rifle scopes allow you to precisely aim a rifle at different targets by aligning your eye with the target at range. They do this through magnifying the target by making use of a set of lenses inside the scope. The scope’s alignment can be adapted for the consideration of many environmental aspects like wind and elevation increases to make up for bullet drop.

The scope’s purpose is to help shooters understand exactly where the bullet will land based upon the sight picture you are seeing via the scope as you align the scope’s crosshair or reticle with the target. The majority of modern-day rifle scopes and optics have about 11 parts which are found internally and externally on the scope body. These optic pieces consist of the rifle scope’s body, lenses, elevation dials or turrets, objective focus rings, and other elements. Learn about the eleven parts of optics.

Rifle Glass Styles

Rifle scopes can be either “first focal plane” or “second focal plane” type of optics. Considering the best type of rifle scope is based on what type of shooting you plan to do.

About First Focal Plane Scopes

First focal plane glass (FFP) come with the reticle in front of the magnifying lens. This triggers the reticle to increase in size based on the extent of magnification being used. The outcome is that the reticle measurements are the same at the amplified range as they are at the non magnified range. For example, one tick on a mil-dot reticle at 100 yards without “zoom” is still the exact same tick at one hundred yards with 5x “zoom”. These kinds of scopes are beneficial for:

  • Quick acquisition, far away kinds of shooting
  • Shooting situations where computations are marginal
  • Experienced shooters who know their target “hold over” as well as “lead” correlations for their rifles
  • Shooters who do not mind the reticle is enlarged and uses up more visual eyesight area than a SFP reticle

Info on Second Focal Plane Optics

Second focal plane scopes (SFP) include the reticle behind the zoom lens. This triggers the reticle to stay at the exact same dimensions in connection with the amount of zoom being used. The final result is that the reticle dimensions adapt based on the magnification chosen to shoot over longer ranges because the reticle measurements represent different increments which change with the zoom level. In the FFP illustration with the SFP glass, the 5x “zoom” 100 yard tick would be 1/5th of the non “zoom” tick. These particular varieties of optics are handy for:

  • Far away kinds of shooting where shooters have increased time to make ballistic estimations
  • Shooting where most of the shots happen within shorter ranges and proximities
  • Shooters who desire a clearer optic picture with less space used up by the enlarged FFP reticle

Rifle Glass Zoom

The quantity of scope magnification you need on your scope depends upon the type of shooting you like to do. Almost every kind of rifle optic supplies some degree of zoom. The level of zoom a scope supplies is determined by the diameter, thickness, and curves of the lenses inside of the rifle scope. The magnifying level of the optic is the “power” of the glass. This signifies what the shooter is observing through the scope is magnified times the power aspect of what can generally be seen by human eyes.

About Fixed Single Power Lens Scopes

A single power rifle scope and optic will have a magnification number designator like 4×32. This indicates the zoom power of the scope is 4x power and the objective lens is 32mm. The zoom of this type of optic can not fluctuate since it is a set power scope.

Adjustable Power Lens Glass

Variable power rifle scopes can be changed between magnification increments. It will note the magnification level in a format such as 2-10×32. These numbers mean the magnification of the scope could be set between 2x and 10x power. This additionally incorporates the powers in-between 2 and 10. The power adaptation is accomplished utilizing the power ring component of the scope near the rear of the scope by the eye bell.

Power and Range

Here are some suggested scope powers and the ranges where they may be successfully used. Consider that higher magnification glass will not be as practical as lower powered scopes due to the fact that increased magnification can be a bad thing. The very same idea applies to longer ranges where the shooter needs increased power to see exactly where to properly aim the rifle.

Rifle Optic Lens Coating

All state-of-the-art rifle scope and optic lenses are layered. Lens finish is a crucial aspect of a rifle’s setup when buying high end rifle optics and scope setups.

HD Versus ED Glass Lens Coatings

Some rifle glass producers also use “HD” or high-definition lense coatings that make the most of various procedures, chemicals, components, and polarizations to extract separate color ranges and viewable target visibility through the lens. This high-definition finishing is commonly used with higher density lens glass which decreases light’s chance to refract through the lens glass. Some scope brands use “HD” to describe “ED” suggesting extra-low dispersion glass. ED handles how colors are represented on the chromatic spectrum and the chromatic aberration or deviance which is similarly called color distortion or fringing. Chromatic aberration can be visible over things with hard edges and shapes as light hits the object from certain angles.

Details on Single Coating Versus Multi-Coating

Various optic lenses can also have different finishes applied to them. All lenses usually have at least some type of treatment or finishing applied to them prior to being used in a rifle scope or optic.

Single layered lenses have a treatment applied to them which is generally a protective and enhancing multi-purpose treatment. This lens treatment can safeguard the lens from scratches while decreasing glare and other less useful things experienced in the shooting environment while sighting in with the optic. The quality of a single covered lens depends on the scope designer and how much money you paid for it. The scope’s maker and cost are indications of the lens quality.

Some scope manufacturers also make it a point to define if their optic lenses are covered or “multi” covered. This means the lens has had several treatments applied to them. If a lens gets multiple treatments, it can show that a manufacturer is taking multiple actions to combat different natural factors like an anti-glare finish, a scratch resistant anti-abrasion covering, followed by a hydrophilic finish. This also doesn’t necessarily imply the multi-coated lens will perform much better than a single layered lens. Being “much better” depends upon the producer’s lens treatment solutions and the quality of materials used in creating the rifle scope.

Hydrophobic Finishing for Glass

Water on a lens doesn’t help with keeping a clear sight picture through a scope at all. Many top of the line and military grade scope companies will coat their lenses with a hydrophilic or hydrophobic coating.

Glass Mounting Options

Mounting solutions for scopes come in a few choices. There are the standard scope rings which are individually mounted to the scope and one-piece scope mounts which cradle the scope. These various types of mounts also normally come in quick release variations which use manual levers which permit rifle shooters to quickly mount and remove the optics.

Hex Key Rifle Glass Ring Mounting Solutions

Basic, clamp-on design mounting scope rings use hex head screws to fix to the flattop design Picatinny scope mounting rails on rifles. These kinds of scope mounts use two separate rings to support the scope, and are normally made from 7075 T6 billet aluminum or similar materials which are developed for far away accuracy shooting. This form of scope mount is good for rifle systems which need to have a long lasting, unfailing mount which will not change regardless of how much the scope is moved or jarring the rifle takes. These are the style of mounts you want for a dedicated scope setup on a long distance hunting or competitors long gun that will rarely need to be modified or adjusted. Blue 242 Loctite threadlocker can additionally be used to prevent the hex screw threads from wiggling out after they are installed tightly in position. An example of these rings are the 30mm type made by Vortex Optics. The set normally costs around $200 USD

Quick-Release Cantilever Scope Rings

These types of quick-release rifle scope mounts can be used to rapidly detach a scope and attach it to a different rifle. Multiple scopes can even be switched out if they all use a compatible style mount. These types of mounts come in handy for rifle platforms which are carried a lot, to remove the optic from the rifle for protecting the scope, or for optics which are used between numerous rifles.

Sealing and Gas Purging for Optic Tubes

Moisture inside your rifle scope can ruin a day of shooting and your pricey optic by triggering fogging and producing residue inside of the scope tube. A lot of scopes prevent moisture from entering the scope tube with a system of sealing O-rings which are water resistant.

Gas Purged Optic Tubes

Another element of preventing the accumulation of moisture inside of the rifle optic tube is filling the tube with a gas like nitrogen. Given that this area is currently occupied by the gas, the optic is less impacted by condition shifts and pressure differences from the outdoor environment which could potentially allow water vapor to leak in around the seals to fill the void which would otherwise be there. These are good qualities of a decent rifle scope to seek out.

Additional information

Category

Rifle Scopes

Brand

Monstrum

ASIN

B08KSJD8VR

Reviews

Over 1

Reviews Rating

5.0 out of 5 stars

Prime

Amazon Prime

Shipping

FREE Shipping by Amazon

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Last update on August 19, 2026 // Source: Amazon API

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