Do I need a Bubble Level on my Rifle Scope?

Ade from Optics Warehouse provides a detailed explanation of the benefits of using a Bubble Level with your Optic.

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A very small but invaluable piece of equipment that is more than often overlooked is the Bubble Level.

For range work especially - but invaluable to the Hunter also - when shooting at long distances i.e. anything regularly shot out beyond 300+ yards, then professionals agree that the use of an ‘Anti-Cant’ Bubble Level really is a must!

The reason being, using a Bubble Level will almost certainly help you in eliminating the trait of horizontal drift of the bullet caused by scope cant error.

(On many occasions we have conversations regarding scope errors and undoubtedly with some of these, Scope Cant could be a contributing factor.)

A Scope Bubble Level is recommended when target shooting over medium to long distances and requires fitting to your Scope tube body. This then ensures that the Scope is perfectly upright. (Of course, ideally, you will already have a Picatinny level attached to your firearm etc to ensure this is also a level platform.)

Once complete, the Bubble Level must be checked before taking a shot.

[Image courtesy of ShootingIllustrated.com]

The above image, although exaggerated, shows what can happen.

[Image: MK Machining]

So treat a bubble as you would a Zero Stop function.

Checking the orientation of the scope with a Bubble Level will give you a starting point each time, rather than dialing in corrections, which can be meaningless if the Rifle is not at the exact same point of upright as before (no cant).