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

  • Based on 426 reviews
Condition: Used - Like New
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Color: Flat Dark Earth


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: Flat Dark Earth


Style: Heavy Duty


Sport: Hunting


Material: 6061 Aircraft Grade Aluminum


Magnification Maximum: 18 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Brand: ‎Monstrum


Color: ‎Flat Dark Earth


Style: ‎Heavy Duty


Sport: ‎Hunting


Material: ‎6061 Aircraft Grade Aluminum


Magnification Maximum: ‎18 x


Objective Lens Diameter: ‎50 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: ‎850017827059


Item Package Dimensions L x W x H: ‎15.59 x 6.06 x 3.54 inches


Package Weight: ‎1.65 Kilograms


Brand Name: ‎Monstrum


Warranty Description: ‎Full Lifetime Warranty


Part Number: ‎G3F31850-FDE


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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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: 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

  • Almost perfect.
Color: Flat Dark Earth
After about 500 rounds on three guns (which is great to show it zeros and ease of adjustment, but long term zero remains to be seen) my impressions are: It's a very good scope in its weight class, the glass is very clear and the adjustments are clean and responsive. The only problem with adjustments were that my red/green illuminator knob is a bit messed up and finicky. This is not a huge deal for me since I don't plan to use it all the time, but I did pay for that feature, and it doesn't work. It's a 50mm scope, so it's freaking big, but it's bright and FOV is great. It's borderline comically long with the sunshade, and almost bulky. The glass is pretty clear in the center, with low distortion on the edges. Any other grievances I have with this scope are with the reticle and subjective, many border on wanting to have my cake and eat it too. The reticle is very thin if you want to actually use it at 3x, especially without illumination, but I recognize this keeps visibility great. The reticle is great balance of giving information without being busy. But that 1 MOA center dot really is the Achilles heel of this scope in my opinion. 1 MOA at 800 or 1000 yards is pretty big in regards to long range precision, or the air rifle community, who I'm aware use these products. and shrinking that dot to match the adjustment would be a massive improvement in my opinion. ... show more
Reviewed in the United States on November 14, 2025 by Jordan

  • Great product
Color: Flat Dark Earth
Great product, highly recommended.
Reviewed in the United States on December 8, 2025 by danilo lopez jr

  • 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

  • Ok scope for the money
Color: Black
I've used a lot of Monstrum products over the years and this is a first. It's labeled as 1 lb 5 ounces. Scope, rings, and lens caps is actually 2 lbs 2.3 ounces. Retical is rather small at 3x but glass is clear. Rings that come with the scope are nothing spectacular but are rigid enough for a hunting rifle. Lens caps are a soft rubber that open and close nicely. Illuminated Retical does put a little glow in the glass when on the higher 3 settings. Is this a scope for extreme long rang shooting in my opinion no. But it's as good if not better than scopes out there that are 2-3 times the money. For 90% of the people out there this scope is more than enough for what you are doing and more capable than the shooters skills. ... show more
Reviewed in the United States on January 25, 2025 by DDUB

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