Monstrum 1-4x20 Rifle Scope with Rangefinder Reticle and Medium Profile Scope Rings
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Color: Black
Features
- Tactical rifle scope providing crystal clear targeting at 1-4x magnification, with a 20mm objective diameter and an eye relief of 3.5-3.8 Inches
- Glass rangefinder reticle for on-the-fly range estimation and long distance targeting
- Lever controlled reticle illumination in both red and green with multiple brightness intensities
- Includes set of 1 inch high profile scope rings
- Aircraft grade aluminum construction with a 1 inch sealed, nitrogen charged tube for resistance to water and fog
Brand: Monstrum
Color: Black
Style: Tactical
Product Dimensions: 8.5"L x 2"W x 1.8"H
Sport: Hunting
Item Weight: 11 Ounces
Material: 6061 Aircraft Grade Aluminum
Magnification Maximum: 4 x
Objective Lens Diameter: 20 Millimeters
Magnification Minimum: 1 x
Brand: Monstrum
Color: Black
Style: Tactical
Product Dimensions: 8.5"L x 2"W x 1.8"H
Sport: Hunting
Item Weight: 11 Ounces
Material: 6061 Aircraft Grade Aluminum
Magnification Maximum: 4 x
Objective Lens Diameter: 20 Millimeters
Magnification Minimum: 1 x
Compatible Devices: Rifle
Mounting Type: Picatinny Mount
Night vision: No
Eye Relief: 3.5 Inches
Field Of View: 105.8 Feet
Model Name: S1420-R-RG
Manufacturer: Monstrum
Reticle Type: Rangefinder
UPC: 740016797265
Item Package Dimensions L x W x H: 11.85 x 3.27 x 2.52 inches
Package Weight: 0.6 Kilograms
Item Dimensions LxWxH: 0.33 x 0.03 x 0.03 inches
Brand Name: Monstrum
Part Number: S1420-R-RG
Included Components: 1-4x20 SFP LPVO Scope, 1 inch Medium Profile Scope Rings, Lens Cleaning Cloth, Manual
Date First Available: May 20, 2013
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If you place your order now, the estimated arrival date for this product is:
within 30 days
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
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View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Top Amazon Reviews
Color: Flat Dark Earth
I figured I could get away with a cheaper scope since I was putting it on a Ruger 10/22 and I really didn't expect much for this price point. However, even as I unboxed it, the quality was evident. This thing is sturdy, the lenses are clear, and the crosshairs are sharp! Zeroing was easy and I was clover-leafing my groups at 25 yards. I've put about 300 rounds through with this scope and it holds zero (not surprising on a 0.22. I may slap it on my 30-30 just to see if it can take the punishment. In any case, I am really happy with this scope.
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Reviewed in the United States on July 2, 2025 by J. Hewlett
Color: Black
Bought it for my 17mach2 it good for what I bought it for. Full magnification is clear at 100yards. Good to use for plinking or varmit removal.
Reviewed in the United States on June 9, 2025 by Jay
Color: Black
I put it on a 45-70 and I'm not sure how long it will last, but the glass is very clear and I'm very happy so far
Reviewed in the United States on March 23, 2025 by Travis & Shawna Travis & Shawna
Color: Black
This is my fourth Monstrum optic, though my first LPVO from them. I wanted a lower price LPVO for a 12ga slug gun, and as with all.my previous Monstrum scopes, this one performed extremely well. I held up very well to the shock of a 12ga slug in a Remington 870, and held zero with no issues. Easy to dial in, and it stayed there. No noticeable parallax issues, great sight picture and eye box, no significant edge blurring, and as always with Monstrum, very generous eye relief (which was necessary considering that 12ga kicks hard). Is the glass as clear as my Sig Tango? No. But for this, I didn't need it to be. Next time I need a good LPVO, I'll look at some of Monstrum's higher end, yet still vastly affordable, offerings. If you're looking for a good LPVO at an excellent price, this one is as good or better than a Primary Arms, and almost on par with a very pricy Sig.
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Reviewed in the United States on December 4, 2024 by Amazonian Customerers
Color: Black
My second Monstrum, and I don't regret this one. Granted, you can get Primary Arms for same price (when on sale) but my big thing is, 1" tube diameter. Go ahead and look see how many LPVO's you can find with 1" tube... The glass is OK clear, nothing came loose after shaking it like a maniac for 5 minutes, but didn't do a drop test... yet. The diopter adjustment is ok, even though you might have a tough time if you're in the + side with your vision. Has a mini throw aluminum lever which I loctite'd (new word) - makes the zoom wheel turning fairly easy. On the left side, this proof that proof message in white letters is clearly visible when you mount the scope, so that's a little cheap looking, maybe I'll cover it with a sticker. Also, comes with this weird battery (two of them) - not your standard 2032 or 2025. Has orange "glass" bikini lens cover, which is a'right - keeps things from getting overly dusty. The reticle, not my super fav, but illuminates abundantly in both red and green - 5 settings each with no 0 stops between levels with the knob set on the left at 45 degree angle, close to the eye viewer. Turning was ok - not too hard, however the battery door gasket will bunch up on you if you tighten it fast and furious, so three finger it, Mercedes logo style, slowly. Windage and elevation turrets are small to medium height, and very nicely clikety and tactile, even though they don't snap on a setting like a Swiss clock - so it's a bit mushy. And scope rings are included - medium size. Bottom line, a head turner it is not. But, it doesn't need to be. Hopefully, gets the job done, after going on a 44mag lever with full loads, not Special. That'll really bang it around good, hoping it'll come out alright and keep on ticking.
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Reviewed in the United States on December 30, 2022 by C. Andrea
Color: Black
The scope could not hold zero. After about 200 rounds through my .44 magnum Henry lever gun, I was becoming really puzzled as to the massive differences in my groupings. Then I tried DRY FIRING the rifle, and that is when I noticed drastic changes in windage and elevation. The reticle was unable to hold zero upon dry firing the rifle! Absolutely do not recommend.
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Reviewed in the United States on April 27, 2025 by Conner Fenner
Color: Flat Dark Earth
honestly, with this feature set and robust built quality you're not going to do better for a sub $100 scope, you're just not, the glass is clear and fairly bright, eye relief is optimal, and the thing just has a great build quality, it's a bit on the heavy side due to this, but what do you expect? it's can;t be well built, lightweight and affordable, such a beast does not and simply cannot exist, quality lightweight materials cost money, sure you can buy a cheap light weight scope but one slip or fall and that piece of garbage is likely toast....seeing as how you couldn't hit the broadside of a barn even with this scope, you could club a man to death over the head with it and it'd still likely be functional and holding zero. i'm a big fan of PA and vortex, a vast majority of my rifles have stuff from those guys on them, i bought this one because it was one of the few scopes that came in FDE and needed something cheap to go on a range toy AR-47 that i put together, turns out this thing is pretty darn nice and is sitting on my scar17 for the moment until i can get the money together for a razor HD or Acog, but in the meantime this seems to have held up to the recoil well and looks at home there, just to be clear, this is not a $1,000 scope, don't expect it to perform as such, in the price range that this scope competes with though is is top notch, you're only chance to do better would be a going with a non-illuminated, BDC reticled, fixed power scope of sorts...and that doesn't sound like much fun! as i've said, this thing has a great feature set and is well built, i expect it to out last any of the other, now flimsy feeling, weaver type scopes i'm currently using and will probably come back and buy another couple of these for rifles where it makes sense for a 1-4 scope. i should also say that dials and adjustment all fell super solid as well, everything on this scope is just solid. the integrated throw lever is a nice touch as well. nobody has given me anything of any sorts to say any of this,....bummer, lol, i still wonder how all of these people get free stuff all of the time, ....probably because my reviews suck. lol
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Reviewed in the United States on April 23, 2017 by THEIZZARDKING