Installing a scope properly is a key element in ensuring both the performance of your rifle and your ability to enjoy shooting it. A good opinion is that your scope needs to be set at a level where it optimizes your comfort and the ease of firing. But even considering comfort level, could a high scope ring negatively affect your line of sight? For long-distance shooting, can a high scope ring make it more difficult to compensate for targets beyond point-blank range?
When possible, employ lower scope rings. They will increase point-blank range and allow a flatter angle to aim at long-distance targets. However high rings are helpful for scopes that require frequent adjustment or for extremely long-range targets.
Take a look at some of the factors that you need to be mindful of as you determine the proper ring size.
How High Should My Scope Rings Be?
The most important consideration is to make sure your ring height allows your face to comfortably rest in the cheek weld. With your face resting in the cheek weld, you will need to make sure your eyes are looking at the scope’s reticle at a level angle.
If either of these factors are off, you will move your head or body to compensate. This movement increases both your discomfort but also your accuracy, as you will either tilt the barrel while firing or aim off-center through the scope.
1.5 inches from the center line of the bore to the center of the scope is a fairly standard measurement used in ballistics sight height. However, this number doesn’t give you enough information to determine which rings you should use. For a larger scope (e.g., 34 mm), you would want to use a low ring, but a 1-inch scope would require either a medium or high ring.
But other variables also play into the ring size you may wish to use for your scope.
Point-blank range is the distance a bullet can be fired without compensating for gravity. The general rule is, the higher the sight height, the shorter point-blank distance will be. This is not because the laws of physics somehow change for the bullet. Rather, sighting squarely from a greater sight height will cause more tilt in the barrel. When a bullet is fired at an angle, it will travel a shorter distance than a bullet fired on a level trajectory before gravity’s impact affects its flight.
Lower rings are preferable for shooting at very small targets over distances of several hundred yards. This is simply because the lower sight reduces the distance in which the bullet will not travel at a straight trajectory. As such, it leaves you a little more margin for error.
Extending point-blank range with a lower ring does have a drawback. While your true (or straight) trajectory will last longer, you may not be able to adequately adjust your scope’s elevation to compensate for the bullet drop at extreme long ranges (i.e., 500 yards or more). A higher ring may require a bit more fine-tuning for determining the best trajectory. But the extra few millimeters above the barrel will give you greater adaptability for hitting maximum-range targets.
Point of Aim (POA) versus Point of Impact (POI)
For a properly mounted scope, the correlation between POA and POI is better on most rifles with lower scope rings. The exceptions to this are guns that have special accessories like the AR-15. However the scope ring is not the only factor that can negatively impact the distance between POA and POI.
However, if you are having problems with POA/POI on any ring height, make sure your rings are not misaligned. It is easy to make an error when installing the base mount or the ring on top of it. A good installation means that the scope is perfectly parallel with the barrel. The slightest error can create the slightest angle in the scope bore. This will cause major discrepancies between the POA and the POI, no matter what size scope ring you use.
Your scope height has a negligible effect on the recoil that you feel as you fire the rifle. But recoil vibration does increase on extremely high rings, leading to potential damage to your scope. Granted, nearly all scopes are designed to withstand recoil. But no scope is immune to damage. The narrow connection of a high scope ring can channel extra resonance into and through your scope. Long-term exposure to this increased recoil can break the scope. Keep to standard ring sizes, and you should not have to worry about the effects of this added recoil.
Ultimately the height of your scope ring is a custom decision. Lower rings eliminate some potential problems. But you may find a higher ring will provide greater comfort. Avoid extreme low or high rings, and you will undoubtedly determine a ring height that will suit your pleasure – and your accuracy!