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Monstrum

Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment

    • Based on 1,122 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Tuesday, May 21
Order within 16 hours and 3 minutes
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Style: Guardian | 4-12x50 AO


Features

  • Adjustable 4-12 times magnification, for targeting out to 800 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
  • Precision 1/4 MOA/click windage and elevation adjustments with locking turrets
  • Package includes High Profile Picatinny/Weaver Scope Rings and set of flip-up lens covers

Brand: Monstrum


Color: Black


Style: Guardian | 4-12x50 AO


Sport: Hunting


Item Weight: 15 Ounces


Material: Aluminum


Magnification Maximum: 12 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 4 x


Compatible Devices: Rifle


Brand: ‎Monstrum


Color: ‎Black


Style: ‎Guardian | 4-12x50 AO


Sport: ‎Hunting


Item Weight: ‎15 Ounces


Material: ‎Aluminum


Magnification Maximum: ‎12 x


Objective Lens Diameter: ‎50 Millimeters


Magnification Minimum: ‎4 x


Compatible Devices: ‎Rifle


Mounting Type: ‎Picatinny Mount


Night vision: ‎No


Eye Relief: ‎3 Inches


Item Package Dimensions L x W x H: ‎15.98 x 3.39 x 3.03 inches


Package Weight: ‎0.94 Kilograms


Brand Name: ‎Monstrum


Manufacturer: ‎Monstrum


Part Number: ‎SG41250AO-B


Included Components: ‎Guardian Scope, One Pair High Profile Scope Rings, One Pair Spring-Loaded Flip-up Lens Covers


Date First Available: August 23, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, May 21

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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Top Amazon Reviews

    • MONSTRUM ALWAYS PROVIDES QUALITY AT AN EASILY AFFORDABLE PRICE!
Style: Guardian | 6-18x50 AO
My Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment, is a Second Focal Plane scope (my preferred Focal Plane for long-range shooting [750yds+]). The glass is perfect (clear, sharp presentation of illuminated crosshairs, and no halo or fog), and the 1" tube is solid and well made. The 1/4 MOA/click windage and elevation adjustable turrets have screw-on covers to keep your adjustments secure once zeroed, and the clicks are smooth and positive. I have a couple of scopes costing 10 times more than the Monstrum Guardian Series AO Rifle Scope, and I bought it "just to check it out" because of the low-end price. I have used several Monstrum cantilever mounts, and other Monstrum products which impressed me enough to try their optics, and the Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment surpassed my expectations. Monstrum provides an outstanding scope at a bargain price in the 6-18 power range. You are reading this review, and I have NO association with Monstrum other than as a customer, so if you're looking for a 6-18 variable optic, I STRONGLY recommend the Monstrum Guardian Series AO Rifle Scope! If you don't like it and bought it from Amazon, you can return it for credit or replacement. ... show more
Reviewed in the United States on December 5, 2023 by Gil
    • Fantastic 10/22 optic
Style: Guardian | 4-12x50 AO
I bought this to replace the Viridian junk that came mounted on my 10/22. It's simply awesome. Great eye box, wonderful eye relief, and that big 50mm objective lets in a ton of light; so much so I haven't even needed the illumination at the range. I will say that there is a lot of light bleed at the higher settings of illumination, but as none is typically necessary, it's not a big deal at all. The throw lever is a bit stiff, but is starting to smooth out under use. The picture is clear at all magnifications, and the adjustable objective is a game changer. I've never used an AO scope before, MD this is just fantastic. Unlike the POS it replaced, I see a clear target instead of fuzzy mush. While I don't know if it'll hold up to larger calibers, for .22 it's fantastic. The price point is almost ridiculous for a scope like this. I would 200% buy it again. ... show more
Reviewed in the United States on January 8, 2023 by Amazon Customer
    • Nice!
Style: Guardian | 3-9x32 AO
First off it is a well built scope. Looks great and perfect size for my setup. The only thing that keeps it from being a 5 is that the turrets aren't as tactile as I would prefer. Overall a good scope for the money!!!!!
Reviewed in the United States on November 10, 2023 by Lorenzo
    • Best Optic For The Money...Period
Purchased a Ruger Precision .22lr to see if I liked the platform before I went with it for a 6.5 Creedmor. As the RPR .22 was only $350 I felt a little silly mounting a Burris or Leopold optic on a range toy. Saw the reviews on the Monstrom sights and figured for this price I would be getting an optic with lots of corners cut in build quality and components. It's cheaper than a box of good ammo so I really thought this would be on my rifle for one range trip then end up in my box'o'' old parts. Well I was surprised by the build quality. The tolerances on the tube, adjustment points, and even the mount felt and looked really good. Optic is a bit heavier than the specs but I will let that slide as it's a couple ounces. The glass that I thought would be super cheap with irregular appeture and poor clarity was pretty clear. This does not have the pristine image and sharp clarity of a Leupold's VX entry optic but you are paying $300 less. I have ZERO complaints about the quality and construction of this optic for less than $60 bucks. It exceeded my admittedly very low expectations by a wide margin. The reticule is also very basic and the manual did not provide adequate explanation of the mils appropriate caliber and load to provide what I think is a requirement for this style reticule. Don't think your getting a true FFP range finder finders on this glass. But, again it's a 50 dollar scope you shouldn't. The AO dial did allow a guesstimate of the distance to target by assessing the optical sharpness. It is a feature that you really should not see at this price point and it works. That is probably because the biggest surprise of this optic was the glass. It is not just adequate I would definitely say it is very good. The parallax adjustment was not spectacular but was comparable to what I would expect on a mid range Burris or Vortex. Bottom line it's good glass that allows for an adequate range calculation and provides a more than adequate visual acuity even at 9x. Again, I have seen better but this is the best glass and controls you will get for the money So I mounted this shockingly good quality optic to the Ruger and headed to the range. Mount was super easy, it's a picatinny if you can't figure it out you should not be playing with a firearm. So I started at 100 yards and was off paper the first shot at min magnification. Turned the elevation and windage dials one rotation unit each and missed again. Gave them a couple more twists and I was on paper. Took a couple shots to figure out the mils, which are set to I think 62 grain 5.56 or .223, definitely not a .22lr. I took a couple more shots from a full mount and got the feel for the reticule mils and the drop on the Hornady .22 I was firing. I pulled back to 50 yards and found zero in a 3 shots Pushed back out to 100 and was able to get a good zero after learning the system and adjustments. The Optic was a bit more than the round I was shooting should have so I put that on me underestimating the Scope. Windage and Elevation have nice firm click and resistance. Once you know what a rotational unit is going to do this optic is easy to zero. The Mag and AOcontrols worked well and the parallax was minimal. Eye relief was excellent. I was shooting a bolt action precision chasis rifle so recoil was almost non-existent. That said this optic easily held zero over probably 200 shots that day. The caps were ok more than I expected but the cheapest feeling component of the system. I have to say I was blown away that a scope with the quality and accuracy of this optic was in junk toy scope price range. Is it a $2,000 scope NOPE. It is comparable or better than many $300 - $500 dollar optics I've had from Burris and Vortex. Best damn scope I've ever used that was $50 bucks without a doubt. The Monstrum never went in the box'imparts it is still on the Ruger. Shoots great. For the money this is a no brainer and could easily be used with .223 or .270. I'm not sure how it would handle .308+; but it probably would hold a zero and be a great optic for hunting open terrain. I can't say this and mean it more, if your learning to distance shoot this is would be a great way to learn fundamentals. Without breaking the bank. A low end Rem 700 and this scope will leave you hundreds to spend on instruction and practice ammo. It exceeds all expectations and will give you a scope that feels and performs like one that is 6 times it's price. The best optic for your money period. Just don't put one on a Ruger Precision because that is a crack gun and gets you hooked fast and will quickly result in desire for one of his big brothers. I really loved the chasis and trigger and shockingly the optic. I have subsequently added a Alpha FFP1x6 24 to an AR race gun that my buddies all admitted shot as well as their $600+ FFP's. Beginning distance shooters can't go wrong with this high value optic you won't be out shooting your glass anytime soon. Seasoned shooters looking for a bargain or a practice rifle scope will be pleased as well. This optic changed my old rule the optic should be at least the cost of the rifle and double or triple if your going to 1,000+ shots. I can assure you this rifle can out to 200 yards with quality .22lr. It's the round not the optic that is limited the range and the optic was 1/8th the price of the gun. When I get the Ruger Precision in 6.5 I will likely give a G3 Monstrum the first crack at the picatinny rail. That will buy me a ton of rounds to enjoy the gun over the Leupold I would have been saving for months to buy. Fully recommended not just a good scope for the money but just a good scope period! ... show more
Reviewed in the United States on November 13, 2020 by Shannon Credle
    • Quality product
Style: Guardian | 6-18x50 AO
I really like the speedy delivery time. It is a great scope for distance spotting. Great product at a great price.
Reviewed in the United States on November 29, 2023 by Rodger Earll
    • WOW this scope is the real deal !
Style: Guardian | 4-12x50 AO
well worth the money ,I mounted it on a 30 cal air rifle and it was sighted in within 15 shots at 33 yrds the optics are clear and the lit crosshairs are great even for an old man as myself ! I would put this on a 7 mm deer rifle ... yup
Reviewed in the United States on November 14, 2023 by Don Carlson

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