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Monstrum G3 3-18x50 First Focal Plane FFP Rifle Scope with Illuminated MOA Reticle and Parallax Adjustment

  • Based on 411 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Monday, Aug 4
Order within 2 hours and 59 minutes
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Color: Black


Features

  • High performance tactical rifle scope with 3-18x magnification for mid to long distance shooting out to 1000+ yards
  • Functionally designed first focal plane MOA reticle, with easy-to-read ranging information that remains constant regardless of magnification, for faster range estimation and holdover correction
  • Equipped with a parallax adjustment dial that allows for sharper focus of the target image, elimination of parallax, and range estimation
  • Inline dial controlled reticle illumination with multiple brightness intensities, for better reticle visibility in low light environments
  • Package also includes set of high profile picatinny scope rings, a detachable sunshade, a set of spring loaded flip-up lens covers

Brand: Monstrum


Color: Black


Style: tactical


Sport: Hunting


Material: Metal


Magnification Maximum: 18 x


Objective Lens Diameter: 5E+1 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Brand: ‎Monstrum


Color: ‎Black


Style: ‎tactical


Sport: ‎Hunting


Material: ‎Metal


Magnification Maximum: ‎18 x


Objective Lens Diameter: ‎5E+1 Millimeters


Magnification Minimum: ‎3 x


Compatible Devices: ‎Rifle


Mounting Type: ‎Picatinny Mount


Night vision: ‎No


Model Name: ‎G3F31850


Manufacturer: ‎Monstrum


Reticle Type: ‎Type-H


UPC: ‎850017827042


Item Package Dimensions L x W x H: ‎15.71 x 6.1 x 3.5 inches


Package Weight: ‎1.64 Kilograms


Brand Name: ‎Monstrum


Warranty Description: ‎Full Lifetime Warranty


Part Number: ‎G3F31850-BLK


Included Components: ‎G3 3-18x50 FFP Scope, 30mm High Profile Scope Rings, Lens Cleaning Cloth, Spring Loaded Flip-up Lens Covers, Sunshade


Date First Available: October 2, 2020


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If you place your order now, the estimated arrival date for this product is: Monday, Aug 4

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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Top Amazon Reviews


  • "A Versatile and Clear Rifle Scope for the Range"
Color: Flat Dark Earth
I recently purchased the Monstrum G3 3-18x50 First Focal Plane FFP Rifle Scope with Illuminated MOA Reticle for my range sessions, and it’s been a fantastic addition to my setup. This scope is designed for precision shooting, and it’s delivered impressive clarity and functionality for my needs. Quality and Build: The Monstrum G3 feels solid right out of the box. The 50mm objective lens is housed in a durable aluminum body that’s both lightweight and rugged. The turrets are crisp and tactile, with audible clicks for adjustments, and the illuminated MOA reticle is a nice touch for low-light conditions. It comes with lens covers, which are a thoughtful addition for protection during transport. Performance: This scope performs beautifully at the range. The 3-18x magnification range is versatile, letting me zoom in for long-distance shots while still being usable at closer ranges. The first focal plane reticle scales perfectly with the magnification, making holdovers and adjustments intuitive. The glass is clear, with minimal distortion even at higher magnifications, and the illuminated reticle (with multiple brightness settings) helps in dim conditions. I’ve had no issues with zero retention after several rounds. Value for Money: For the price, this scope is a steal. It offers features you’d expect from higher-end models—like a first focal plane reticle and illuminated MOA—at a fraction of the cost. If you’re a shooter looking for a reliable scope without breaking the bank, this is a budget-friendly option that punches above its weight. Minor Notes: The eye relief is decent but can be a bit tight at higher magnifications, so adjust your position carefully. It’s a bit on the heavier side (as expected for a 50mm scope), so make sure your rifle setup can handle the weight. Also, while it’s rated for various calibers, double-check your mounting setup for compatibility. Overall: The Monstrum G3 3-18x50 FFP Rifle Scope is a reliable, high-value choice for range shooting. It’s clear, versatile, and packed with features that make it a joy to use, all at an affordable price. I’m thrilled with its performance—5 stars for quality and functionality! ... show more
Reviewed in the United States on April 3, 2025 by ess2thebee

  • Great Scope
Color: Flat Dark Earth
This is an excellent scope, high quality, easy to use and worth every penny.
Reviewed in the United States on July 3, 2025 by Michael Gomez

  • Decent scope for the price.
Color: Flat Dark Earth
Surprisingly decent glass for the price point. Tactile and audible clicks on turrets. Was able to hit targets out to 700 yards with this scope, parallax adjustment wasn't perfect but clear enough. Held zero with no problem over the 60 rounds I've done so far.
Reviewed in the United States on June 9, 2025 by Mike Karpinski

  • Good value for the price.
Color: Flat Dark Earth
I have had good experiences with Monstrum products, especially scope mounts and accessories like pic rail levels & lens caps. This is my first higher magnification scope. Good glass for the price. Elevation and Windage adjustment knobs have features usually found on higher end models. Nice parallax feature next to illumination knob. ... show more
Reviewed in the United States on April 22, 2025 by Lars

  • Good Price. Not long range.
Color: Flat Dark Earth
The dot on the crosshairs is way to big at the highest magnification. Not to useful for long range shooting.
Reviewed in the United States on June 2, 2025 by Carolyn

  • Better than expected
Color: Flat Dark Earth
I have two 6-24 G2 and G3 scopes and I really like them, but they add significant weight to the rifle for hunting applications. I am not a competition shooter. So hunting applications are more important to me. the 18x on this scope is more than enough for any ethical shooting distance on game. I prefer shooting on 6-9x, but am glad to have the extra boost if needed. The clarity on the scope is far better than I expected. Excellent. The focus is excellent. The parallax adjusts easily and with excellent focus for my eyes. The windage and elevation are easy to use and adjust with excellent feel and audible clicks. The dial can be adjusted to zero. There is no zero stop, but once sighted the dial can be set at zero. I prefer this for hunting applications. The only negative I have on this scope is that the illumination for the reticle is extremely hard to adjust. But, I won't use it very often, so I can live with it. Overall, this scope meets everything I want in a scope for a hunting application. I highly recommend it. I wish I had found this before I bought the 6-24x scopes. For hunting, I like this much better. ... show more
Reviewed in the United States on September 11, 2024 by Glen

  • Well worth the money
Color: Flat Dark Earth
My monstrum fde scope delivered on time. The color matches my fde/black rifle setup. I highly recommend this scope if you're on a budget. It feels like high quality.
Reviewed in the United States on March 27, 2025 by Tyrone Smith

  • customer service is the worst...
Color: Black
customer service is the worst... I have written two letters to ask my questions WITHOUT answers and this is what I wrote, if anyone has an answer please give me your experience on the scope To whom it may concern: Hi... "Monstrum G3 3-18x50 First Focal Plane FFP Rifle Scope with Illuminated MOA Reticle and Parallax Adjustment" bought this scope on 02/07/23 on Amazon question (I'm very confused) I use the Strelock Pro app to execute my shots with my rifle and the reading it gives me when I adjust it with the turrets IS accurate, Example: if it asks for 18 MOA the impact is perfect... BUT when I use the HOLD OVER the 18 MOA the pellet or Slug goes very high. I have to lower the Hold Over to 9 MOA (exactly half) to make an impact. I did tests at various distances in Hold Over and what the streclosk APP asks for, in turrets is accurate, but I have to adjust the hold Over to half exactly, this means that each ten (10) MOA in the reticle is twice the value specified with the scope, it took me a long time to discover this matter. My question is: what am I doing wrong, or what do I not understand? Is there any explanation for this matter? Note: I have another scope mounted on an FX pantera 700mm Element Optics Helix 6-24x50 FFP and the readings I put on the turrets are the same as what I can use if I use "Hold Over" ... show more
Reviewed in the United States on September 13, 2023 by Ramon Cito

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