A Complete Guide to Helping You Choose the Best Best Rifle Scope Anti-Cant Device!
Recommendations and Installation Instructions!
If you are into long range shooting and want consistent shot placement you need the best rifle scope anti-cant device.
There are so many factors that affect accuracy – especially on long range shots. You’ve spent thousands on a scope and rifle with perhaps some special modifications. You might even be using custom hand loads, trying to eke out that last quarter MOA of accuracy. But, if you’re setting up your shots with even a slight cant, all your efforts could be in vain.
The solution is to install an anti-cant device that will tell you if you are holding your rifle and scope in the perfect vertical position. The problem is finding the right one.
There are so many different products available for different mounting options and shooting situations. Finding the best one could mean some frustrating trial and error if you aren’t quite sure what to look for.
I’ve been through the process of installing and using some anti-cant devices on my rifles and I though I would share what I have learned.
What are the Best Rifle Scope Anti-Cant Devices?
There are a lot of products on the market but I can only recommend the ones I am familiar with and confident will work well. I believe these are the best rifle scope anti-cant devices currently available.
#1 Flatline-Ops Sniper Accu Level Articulating Scope Level
- Size/s: 30mm/35mm
- Mounting: Scope
- Recommended For: Precision long range shooting, LE, Special Ops, Sniper
- Type: Articulating
- Features: Made in the USA, High Visibility Fluorescent Fluid, Aircraft Grade 6061-T6 Aluminum, Black Hard Anodized Finish, Stainless Steel Hardware, ADI compatible
It just doesn’t get any better than this! The Flatline-Ops Sniper Accu Level Articulating Scope Level has every feature a serious long range shooter could ask for in a rifle scope anti-cant device.
Unlike most articulating anti-cant devices, this one mounts on your scope, usually without removing it. You can install it for a right or left-handed shooter. It has the high-visibility fluorescent fluid in the level making it easy for your eye to pick up before each shot. Another huge difference is you can make fine adjustments after it has been mounted in both the closed and open position.
The level arm has double detents that make sure it is locked in place before taking that critical shot.
Rock solid construction insures this anti-cant device will stand up to rough handling in all kinds of conditions.
A unique feature of this accessory is it comes with a Dovetail Accessory Lug for attaching the Sniper Tools Military Spec ADI Angle Degree Indicator.
Check Out this Excellent Installation VIDEO!
The Flatline-Ops Sniper Accu Level Articulating Scope Level is a critical part of a sighting system. Just as important as it is to have a dead-on true vertical hold you also need to know the angle that you are shooting.
When aiming up or down the POI needs to be compensated for to make an accurate hit. The Sniper Tools Military Spec ADI Angle Degree Indicator enables you to take the guess work out of your calculations.
As a combo, the Flatline-Ops Sniper Accu Level Articulating Scope Level and the Military Spec ADI Angle Degree Indicator will take your long range shooting to the next level.
#2 US Optics Swivel Anti-Cant Device BBL-300
- Size/s: N/A
- Mounting: Mounts to all 1913 picatinny rails
- Type: Articulating
- Recommended For: All Long range shooting, L.E., special ops, tactical, hunting
- Features: Made in the USA, Precision machined from 6061-T6 Aluminum, Type III Hard Anodized, Screw-on Vial cover, Left or Right mount, easy installation
The US Optics Swivel Bubble BBL-300 is my favorite articulating rail-mounted Anti-Cant Device. The quality of this ACD is evident the moment you open the package. Its precision close-tolerance parts prevent any slop in the swivel joint for shot after shot repeated accuracy.
It can be mounted on the left or right side of your rifle although the articulating level arm only swings one way. It is designed so you can mount it on any 1913 Picatinny Rail without having to remove your scope.
A Word of Caution!
Since the base of this level indicator is relatively small and made from aluminum, care needs to be exercised when installing on your Picatinny Rail. If you over-torque the clamping screw opposite the level, it can distort the base causing to give an inaccurate reading. I believe this issue is the cause of the relatively few negative customer reviews.
A big advantage of this device is that it’s mounted on the scope base so your eye can pick up the level bubble without looking up.
It has a knurled vial cover that protects it while not in use and can be screwed on to the opposite side of the rail clamp for safe storage while shooting. A set of opposing detents locks it in place when open or in the closed position.
#3 Wheeler Engineering Anti Cant Indicator, 1-Inch
- Size/s: 1″ Inch
- Mounting: Scope Tube
- Type: Articulating
- Recommended For: Long range shooting, varmint hunting, tactical, sniper, special ops, LE
- Features: USA Made, Precise Repeatability, Easy-to-View from Shooting Position, Attaches to Scope, Precision Machined Aluminum, Anodized finish
The Wheeler Engineering Anti Cant Indicator is my favorite scope-mounted articulating anti-cant level indicators. Its rugged built with precision CNC machined parts and industrial grade hardware.
One of the features I like about this ACD is the way it locks into position. Instead of using detents which can eventually become worn, this device utilizes an external spring that is loaded against a washer. When you open the level arm it compresses the spring as the washer moves over the rounded corner. When its fully extended it presses it up against a large flat in the hinge joint. This gives the Wheeler Engineering Anti Cant Indicator rock solid repeatability.
Another feature that puts this anti-cant device on my short list is the machined indicator point in the level vial housing. This pointer helps the eye naturally line up the bubble along with the help of the two lines before each shot.
The clamping ring is heavy duty with the top half skeletonized to help offset the weight. The only things I don’t like about the Wheeler Engineering Anti Cant Indicator is because of the size of the clamping ring the scope may have to be removed to install. Also, it only fits 1” inch scope tubes. Other than those two issues this is a top quality rifle scope anti cant device.
#4 Holland’s Signature Series Anti-Cant Scope Level
- Size/s: 1”, 30mm, 34mm, and 35mm
- Mounting: Scope mounted
- Type: Fixed
- Recommended For: Competition long-range shooting, varmint hunting
- Features: American-Made, Sculptured Design complements expensive rifles, Reflective Illumination for Low Light Visibility
The Holland’s Signature Series Anti-Cant Scope Level was designed by long-range shooting instructor Darrell Holland and the official level of the USA F-Class shooting team.
These high quality instruments are machined from 6061 aircraft-grade aluminum and have a hard black anodized finish.
This fixed scope mount level can be mounted for right or left-handed shooters.
One of the distinguishing features of this anti-cant device is the ability to see the level in low light conditions. Holland’s Reflective Illumination produces the easiest to see anti-cant level on the market. It’s designed so you don’t have to strain your neck to see and it doesn’t protrude beyond your windage or parallax adjustments.
This accessory is available in 1”, 30mm, 34mm, and 35mm scope tube sizes to accommodate the most popular F-Class long-range scope models. Because of the sleek, low profile design the bottom half of the clamping ring should fit between most scope/base mountings without removing the scope.
The sculptured design has contoured corners that minimize snagging and they blend with the lines of your scope and rifle. They look as good as they function!
The Holland’s Signature Series Anti-Cant Scope Level is in my opinion the best fixed scope-mounted anti-cant device available. If you are into completion long-range shooting this is the device you should consider. It’s very reasonably priced and available for FREE SHIPPING!
#5 Lone Star Precision Scope Bubble Level Indicator
- Size/s: 1”, 30mm, or 34mm
- Mounting: Scope mounted
- Type: Fixed
- Recommended For: Long-range shooting competitions, varmint hunting
- Features: Precision Made in the USA, Easy and Fast Installation, Ambidextrous Mounting
Proudly made in the Lone Star state of Texas, this Precision Scope Bubble Level Indicator is ideal for serious long-range shooters.
Don’t let the low price fool ya! This is a top quality tool, CNC machined from Aircraft Grade 6061-T Aluminum to 0.0005 of an inch tolerances and hand-assembled in the USA!
Its unique design makes it fast and easy to mount on 1”, 30mm, or 34mm rifle scope tubes, usually without removing the scope. You can install it for right or left-handed shooting.
I have one of these babies mounted on my back-up tactical rifle and I love it! My eyes aren’t as great as they used to be unfortunately. The close-together lines on the bubble vial and the pointer in the center makes it easy for my eye to see when the bubble is exactly centered.
I highly recommend the Lone Star Precision Scope Bubble Level Indicator if you want excellent quality at a modest price. It’s perfect for just about any long-range shooting and it even looks good on your rifle!
#6 Vortex Optics Riflescope Anti-Cant Bubble Level
- Size/s: 1”, 30mm, 34mm, and 35m
- Mounting: Scope
- Type: Fixed
- Recommended For: Entry-level long range shooting, varmint hunting
- Features: Ensures Precise Vertical Hold, Quick and Easy Mounting, Budget Priced
The Vortex Optics Riflescope Bubble Level is one of my favorite budget-priced scope mounted anti-cant devices. The main reasons I like this product is – it works and it don’t cost much!
It is available in (4) scope tube sizes that cover the range of most popular scopes. The lines on the level are close together that makes it easier to line up the bubble for more precise leveling. The lower clamping ring is thin enough to slip between most scope/base combinations without having to remove the scope.
The Vortex Optics Riflescope Anti-Cant Bubble Level is made from machined aluminum with a black protective finish. This product is imported but the quality is good.
This is a good choice for the shooter wants to ensure his/her rifle and scope are aligned precisely vertical but wants to keep the cost down. The Vortex Optics Riflescope Level is ideal for varmint hunting or entry-level long-range shooting.
What to Consider When Selecting an Anti-Cant Device for your Rifle Scope!
Anti-cant devices are pretty basic but there are a couple differences to think about. The main difference is how the device attaches to your scope or rifle.
Scope Mounted: Most anti-cant level devices clamp on the tube of the scope. They can be oriented on the right or left side depending on your preference. This type is usually preferred by long range shooters or varmint hunters and they are usually easy to install.
The only issue some shooters have with a scope mounted anti-cant device is they can snag on brush or clothing. This could present an issue for varmint or long range hunters.
Picatinny Rail Mounted: The anti-cant devices that mount on a picatinny rail or mount typically have a hinge mechanism so they can swing out for use or fold back in when not being used. These are great for AR’s and other tactical rifles, plus they are easy to install. This type of anti-cant device can be clamped on the picatinny rail – usually without removing the scope and checking its level. (SEE: How to Level a Rifle Scope)
When the bubble level is deployed it is below the centerline of the scope making it easy to see. Another advantage to a folding picatinny rail-mounted anti-cant device is they are much less likely to snag on something when retracted.
There are two issues to be considered when it comes to selecting a Picatinny Rail Mounted anti-cant device:
- There can be some slop in the hinge. This is usually only a problem with the cheaper models but it can give you some inaccurate readings.
- The clamping mechanism may not secure the device exactly perpendicular to your Rifle/Scope centerline giving you an inaccurate reading (Certain models have an adjustment that lets you precisely align it after installation).
How to Install a Rifle Scope Anti-Cant Device!
Installing your new anti-cant device is pretty simple but it must be done correctly to be effective. I am assuming that you realize that your scope must be leveled with your rifle for optimum accuracy. If the vertical cross hair of your scope’s reticle isn’t lined up with the exact dead center of your rifle bore an anti-cant device isn’t going to help you much.
So, whatever you do, make sure and check your scope’s alignment before installing and calibrating your new anti-cant device.
Take the time to read my article entitled “How to Level a Rifle Scope.” Depending on the type of rifle scope anti-cant device you decide on you may have to remove the scope from the rings to install it. That’s the perfect time to check the alignment.
Once you have your rifle set up in a gun vise and leveled and your scope leveled to your rifle, level your anti-cant device with your scope and rifle.
Understanding Scope Cant Error!
When a rifle is canted it will cause your point of impact to move in an arc to the right of left (depending on which way it is tilted) and downward.
If you are setting up your shop and canting your rifle and scope just 5° the point of impact will be off by approximately 3.750” at 300 yards. That would be a clean miss on a small target such as a groundhog or prairie dog.
Having your scope mounted so the vertical cross hair is perfectly aligned with the bore is crucial for optimum accuracy. But that accuracy isn’t realized if you are canting your rifle and scope when you pull the trigger. That’s why it’s so important to have a good anti cant device installed on your rifle scope.
My Own Experience
Speaking from my own experience, I never really considered scope cant an issue because I always figured I had good shooting technique. It wasn’t until I became interested in long-range shooting a few years ago that I began to think about just how vertical I was holding my rifle when setting up my shots.
After installing an anti-cant device I discovered that my technique wasn’t as perfect as I thought it was. Even when using a bipod or sandbag rest I was seeing some error. Probably not enough to make much difference at 100 yards but definitely significant at 600 or 1,000 yards. To make consistently good shots at those distances you need to have excellent equipment, ammo, and correct and technique.
Scope cant error especially comes into play when you are doing long range shooting on uneven or hilly terrain. If the backdrop beyond our target is sloped the tendency is to tilt the rifle in the same direction slightly.
Contents at a Glance
- 1 A Complete Guide to Helping You Choose the Best Best Rifle Scope Anti-Cant Device!
- 2 What are the Best Rifle Scope Anti-Cant Devices?