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Monstrum

Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment

    • Based on 871 reviews
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Style: 3-9x40 AO


Features

  • Adjustable 3-9 times magnification, for targeting out to 500 yards and beyond
  • An adjustable objective lens or AO - that allows for sharper focus of the target image, elimination of parallax, and range estimation
  • Precision machined from 6061 grade aluminum, comparable in weight to most scope rings with the added rigidity of a unified one piece mount design
  • All Monstrum Scope products are backed by a two year warranty.

Description

The Monstrum Guardian Series is the latest iteration from our best selling line of SFP rifle scopes! The Guardian 3-9x AO is a full-featured scope suitable for hunting, target shooting, or tactical use, the scope comes equipped with: Adjustable 3-9 times magnification, for targeting out to 600 yards and beyond An adjustable objective lens or AO - that allows for sharper focus of the target image, elimination of parallax, and range estimation Fully illuminated MOA reticle with MOA hashmarks for ranging information and inline dial controlled brightness adjustments Precision 1/4 MOA/click windage and elevation adjustments Anodized aircraft grade 6061 aluminum construction, for lightweight and durable performance An integrated throw lever for smooth and controlled adjustment of the magnification dial A sealed, nitrogen charged scope tube for resistance to fog and water The Guardian 3-9x weighs 15 ounces. It has a 1 inch diameter tube and requires a mount with 1 inch diameter scope rings. The scope is 12 inches in total length. Package includes: A set of high profile scope rings compatible with all Picatinny or Weaver mounting platforms. A set of flip up lens covers One CR2032 battery


Item Package Dimensions L x W x H: ‎15.79 x 3.5 x 3.07 inches


Package Weight: ‎0.9 Kilograms


Item Weight: ‎14 Ounces


Brand Name: ‎Monstrum


Color: ‎Black | Offset Scope Mount


Material: ‎Aluminum


Manufacturer: ‎Monstrum


Part Number: ‎S3940-AO-B


Style: ‎3-9x40 AO


Included Components: ‎3-9x40 SFP LPVO Scope, 1 inch 1-piece scope mount, Lens Cleaning Cloth, Manual


Sport Type: ‎Hunting


Date First Available: September 17, 2019


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Top Amazon Reviews

    • Best Optic For The Money...Period
Style: 3-9x40 AO
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
    • Good for airguns......ish
Style: Guardian | 4-12x50 AO
I figured I'd give these guys a shot the same way I did with vortex when they first started. Very clear glass andfeatures that big brands offer at way higher prices. Second time I turned the red light on for the reticle it stopped working. Green works.....not so much with red. Not sure I'd put it on anything other than an airgun. Works well on a .25 gauntlet. They come with a lifetime warranty so when something else breaks on it I'll send it to monstrum. I would advise checking their actual website before purchasing on Amazon. The 4-12 x 50 I bought dropped from 99.99 on here to 69.99 on their website the day I ordered on here. In the end I wish I had spent a little more on a vortex. I'll come back to these guys if they last another couple years. ... show more
Reviewed in the United States on November 12, 2022 by Bryan
    • A great deal
Style: Guardian | 6-18x50 AO
I admit I have fairly limited experience with long guns, but this scope is really nice and way more than I expected for the price. A great add on to my little deer rifle. I’ll be recommending this brand to friends and family. I am able to see vastly farther than I could ever hope to hit intentionally with amazing clarity. ... show more
Reviewed in the United States on November 24, 2022 by Angie Collins
    • Great features and quality at a great price
Style: Guardian | 6-18x50 AO
Illuminated reticle a must for Low light use. Adjustable objective works for removing parallax.
Reviewed in the United States on December 1, 2022 by $1 Christian Case Maker
    • Basically an airsoft or pellet gun scope
Style: Guardian | 6-18x50 AO
It's basically an airsoft scope the clarity isnt as in the video or description good for 1yrds max got it on my 22 an its decent but nothing amazing you wont be stacking tight groups with this thing
Reviewed in the United States on October 28, 2022 by Robert
    • Awesome scope and I’ll use it for hunting.
Style: Guardian | 4-12x50 AO
It was very clear and for me it’s awesome scope. I use it for hunting.
Reviewed in the United States on November 9, 2022 by Wangdoua Chang
    • Good enough for a back up
Style: 3-9x40 AO
Glass is ok. For the price don’t have to worry about it if it gets banged up
Reviewed in the United States on August 25, 2022 by R-NO
    • Great for the money.
Style: Guardian | 3-9x40 AO
Glass isn’t as clear as my Leopolds, but for the money, a great budget scope. Also built heavy enough to be used as a blunt instrument should you run out of ammo.
Reviewed in the United States on August 8, 2022 by Stephen J. Atherton

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