Monstrum Precision Picatinny Scope Rings | 1 inch Diameter

.8" Rings entirely too low for a 40mm objective lense with an AR platform. If you want to use 40mm optic, get the 1" center height. Even then, the .8" will barely sit the bell of thr scope just above the rail so be weary if you are using a cheek riser. 1" center height WILL NOT work with 50mm objective lense. Other than that, they are made extremely well and have a fantastic finish. Havent checked alignment so not sure if they need lapping.

The basic problem is the machining of the recoil stops on my mounts. One of my mounts fit perfectly out of the box. The second wouldn't mount on the Picatinny rail. The reason turned out to be that one of the mount's recoil stops was machined too wide and both had burrs on them, so it's poor QA. For 17 bucks, I did not want to get into it with the seller and it seemed like a fixable problem. 15 minutes of careful grinding with a Dremel took care of both problems and the mount fits the rail very smoothly with my "adjustments" well hidden. In terms of performance, I selected these mounts because, with their screw locations, they looked like they would be very secure and that has proved the case. Punched out 200 rounds without any backing on the screws. They also sent 4 replacement screws in the package to keep as spares.So, 3 stars because they work well and look good - would have been five had the fit been correct in all particulars.UPDATE: So, during firing on the 200 yd range, the scope barrel began to turn in the mounts - I'm probably about 300 rounds in at this point. Sure enough, the screws on the rings are backing out and had to be re-torqued. At first, it looked like burrs had scratched the scope barrel, but after a bit of cleaning, it was the ring that had worn down and the scope is fine. Can't recommend these things now. Not angry, because they're so inexpensive, just a bit annoyed at myself. Should have pitched them for the recoil stop issue and moved on instead of jury-rigging a solution. Will seek replacements, lesson learned.

Good stuff used them with a vortex 4x12x44It was a good purchase

I try to avoid buying "made in China" items,,, but I will make an exception if it's a "Amazon Prime" item because returns are free and easy to do.Over the years I've tried lots of different scope rings, prices have ranged from cheap (like these) to really expensive,,, what I discovered is,,,, no matter how much I pay, I can still get crappy rings,,,,,, most of the time the issue is apparent just by inspecting them before mounting,,,,, the main issue that isn't so easy to spot is misalignment,,,, I bought a scope ring lapping tool and lap all my scope rings before mounting,,, problem solved.These rings, "Monstrum Precision Picatinny Scope Rings | 1 inch Diameter" required very little lapping and I like that they have a double lug where they sit in the picatinny rail. This is the second set of these rings that I bought and I would buy again.

I just didn't feel like shucking out $60+ for domestically manufactured rings to put a $40 scope on an old, neglected $100 rimfire rifle, so I took a gamble with the $16 Monstrum Tactical 1" low rings. I didn't have any of the negative issues cited by other reviewers; the tops & bottoms lined up nicely, the lugs fit perfectly into a Pic rail, and there were no visible defects in the finish. I lapped them lightly as I always do with scope rings, even though the points of my alignment rods came up needle-to-needle on a test fit before lapping.Note to those experiencing screws coming loose: standard practice is to clean both the screws and the threaded holes they fit with acetone or denatured alcohol. Nail polish remover or 70% rubbing alcohol will do in a pinch, if you give the screws some time to dry or zap them with a hair dryer for a minute. Emplace your scope and lightly bottom out the screws. Then, apply about a 1mm dot of blue thread locker to each screw once you've got the scope into final position.There are several other steps a competent gunsmith will perform to ensure the scope is level, eye relief is appropriate for your expected shooting positions after properly focusing your ocular lens to your reticle, ring gaps and screw tension are even, etc.; novices are well-served to read a book or two or at least view a few YouTube videos on the topic before mounting your scope. There's just a little more to it than turning some screws, but it's nothing the average person can't manage on a coffee table without specialized tools or materials. If you can change the face skin on a PS4 controller or adjust the brakes on a bicycle, you can certainly handle mounting a scope well with these rings.

If the size fits your application these are great for the price. The recoil stops are very reassuring and the whole mounting process was very straightforward and easily accomplished. I couldn't be happier with the fitment and positioning these rings afforded me. 0.8" height used for a Vortex Copperhead 4-12x44 on a Pic rail equipped bolt action. Eye relief and height are perfect on the first go and allow a solid cheek weld. Off to zero in with no hassle.

Bought these to mount a light on a shotgun. Nice low profile, solid mount, and a perfect fit for what I needed. Well made, and a very good quality finish.Update: Bought a couple more sets of these. I normally use a Burris P.E.P.R. mount, but the dovetail to picatinney adapter I have installed on a couple of .22LR rifles places the scope too high. These are perfect! They brought the scope back down to a normal height.