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Monstrum

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

  • Based on 442 reviews
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Availability: In Stock.
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Arrives Thursday, Oct 22
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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

Description

Long Range FFP Scope Target an incredible range with the adjustable 3-18x magnification. Etched Crosshair FFP reticle with red illumination for better visibility. Features a 1/4 MOA windage and elevation adjustments with zero setting. Manufactured from aircraft grade 6061 aluminum. Anti-fog nitrogen charged and weather resistant seals. The Custom Type-H FFP features a 1 MOA dot in the center and 1 MOA between hashmarks with 20 MOA per side and a total of 40 MOA per plane. The reticle illuminates in 11-levels of red throughout the reticle. 1 MOA = 1 inch @ 100 yards. The Custom Type-H FFP features a 1 MOA dot in the center and 1 MOA between hashmarks with 20 MOA per side and a total of 40 MOA per plane. The reticle illuminates in 11-levels of red throughout the reticle. 1 MOA = 1 inch @ 100 yards. The G3F31850 Scope is equipped with a Type-H reticle designed with set hashmarks for estimating distance and for holdover correction. Field of View (FOV) @ 330 Yards: 85.6 - 25.6 ft The G3F31850 Scope is equipped with a Type-H reticle designed with set hashmarks for estimating distance and for holdover correction. Field of View (FOV) @ 330 Yards: 85.6 - 25.6 ft 11-Levels of Red Illumination FFP stands for First Focal Plane. The term refers to the position of the scope reticle in relation to the magnification lens. In FFP scopes, the reticle is located to the front of the magnification lens - the first focal plane. The size of the reticle grows or shrinks in relation to the magnification. All adjustment assemblies are composed of solid brass which make them function smoother and more precise than before. Milled from a solid piece of 6061 aircraft grade aluminum to ensure scope rigidity and strength. This scope has a 1/4 MOA/click windage & elevation adjustments with zero reset and turret locks to prevent slippage.

Brand: Monstrum


Color: Black


Style: tactical


Sport: Hunting


Material: Metal


Magnification Maximum: 18 x


Objective Lens Diameter: 50 millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Magnification Maximum: 18 x


Objective Lens Diameter: 50 millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Thread Type: 30mm


Reticle Type: Type-H


Color: Black


Product Style: tactical


Lens Color: Black


Material Type: Metal


Brand Name: Monstrum


Sport Type: Hunting


Number of Packs: 1


Model Name: G3F31850


Manufacturer: Monstrum


Number of Items: 1


Unit Count: 1 Count


UPC: 850017827042


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


Manufacturer Part Number: G3F31850-BLK


Warranty Description: Full Lifetime Warranty


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Oct 22

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

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • "A Versatile and Clear Rifle Scope for the Range"
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
    • Better than expected
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
    • Not bad at all.
Color: Black
This is my first FFP scope, but feel I can't complain for the price. I have this scope (G3 3x18 50) mounted on my Ruger American bolt action 22lr. I shoot mostly at 25 and 50 yards, and grouping 5 shots in a 1/2 inch square is the norm. The mounts that came with the scope were too high for my liking, but certainly helped me establish a baseline measurement so I could order my preferred height. The eyebox is tight and the view somewhat cloudy at closeup/full mag. The manufacturer claims focus as close as 15 yards, but in my experience 25 yards is fringe at 15 power zoom. Forget about 18x at 25 yards. At full zoom the focus improves with longer distances. The reticle is pretty sweet, and the red illumination looks great. Other notes worthy of mention: I paid full price. I dropped the scope from a height of around 3 feet while removing it from my Henry (to install on my Ruger.) That resulted in a bent sunshade (deformed enough to be noticeable) but doesn't seem to affect the internals. And the lens cap still fits/works! Sometimes, after I've zeroed a turret, the numbers don't always align to the "zero hash" on the scope body. ...I've only zeroed the scope about three times, so maybe it's my technique. TL/DR: Unless something negative pops up in the future, I'll consider buying another. ... show more
Reviewed in the United States on December 5, 2022 by Jack
    • Monstrum 3x18 FFP
Color: Black
I have to admit, I really like this scope. I have it on my Howa mini. Clear glass, like unbelievably clear at this price point! I have spent good money on scopes that have glass this good! So I bought another one for my 22 mag. Not sure what long term durability will be like as I haven’t dropped the rifle. It always returns to zero after returning the turrets to the zero setting. Audible and firm detents on the turrets. Low light visibility isn’t as good as my Nikon but I didn’t pay $800 for this scope either. It’s good, but not great even with an 50mm lens. And I really like the FFP. ... show more
Reviewed in the United States on December 27, 2025 by JH
    • Great scope
Color: Black
I purchased this scope to give it a try. The price was too hard to pass up for a ffp scope with brass internals and all the other features. I was surprised with the clarity of the optic, it tracks very well, holds zero, and the reticle is easy to see at all magnification levels. I did notice that when you get to the top of the magnification level, the eye box can be a little finicky. It can be a bit harder to get the right angle to see through to get the sight picture. You just have to take your time and get lined up behind the scope. I’ve seen other people complain about the center dot when at top magnification. At top magnification, the center dot will match a one inch circle on the target at 100 yards. This scope is on a hunting rifle, so this doesn’t bother me. I also had no issues taking shots out at further distances than 100 yards. I think this scope is a good value. I’m happy I purchased it. It will serve its purpose perfectly for me. ... show more
Reviewed in the United States on February 21, 2023 by Josh Freed
    • Very nice scope kit, but Adjustable Objective is an issue at its lower magnifications
Color: Black
The Adjustable Objective on the Monstrum G3 3-18x50 seems to not be documented anywhere. At lowest magnification I was unable to get a sharp image under 35-40 feet, and while I could see my target to shoot it was blurry and not precise. Greater distances, lets say 30+ yards the AO is fine. Essentially this is a long distance scope only. I returned this scope and went with a 4-16x44 scope from another brand that has much better AO at lower magnifications. I do have the Monstrum G3 6-24x50 which also doesn't document its minimum AO and is also a longer distance scope but seemed to have better AO at lower magnification than the 3-18x50 but still blurry. I would like to see Monstrum offer similar affordable long distance scope with better lower magnification AO. ... show more
Reviewed in the United States on November 12, 2024 by Shane R.
    • Monstrum G3 3-18x50 first focal plane FFP Rifle Scope
Color: Black
I ordered this scope for one of my dad's gun's. He is very happy with it.
Reviewed in the United States on August 23, 2026 by Amazon Customer
    • Will purchase again if needed
Color: Black
Purchased this for my 220 Swift, easy to install, love all the extra functions on this. Site it crystal clear, and eye relief is so much better than some of my high end scopes in the past
Reviewed in the United States on April 17, 2026 by Wade

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