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The ABC’s of Long-Range Shooting: Eye Relief, Reticle Picture, Ballistic Coefficient, and Cartridge Load

 Every new activity has a learning curve and a set of basic terms. A few basic terms will help with that exciting journey for the person entering the world of long-range shooting.

Proper Eye Relief and Reticle Picture – The distance from the rear lens of the scope to the shooter’s eye is known as “eye relief.” As the scope is being mounted, the shooter needs to shoulder the rifle and find the proper distance from his or her eye to the rear lens. That distance is the point where the shooter can hold the rifle comfortably and experience a complete field of view.

The reticle is the crosshair or central aiming point of the optic. To achieve the best Reticle View or Picture, the shooter needs to adjust the eyepiece, the very rear section of the scope, until that reticle appears sharp and clear. This is easily done by aiming the scope at a wall or even the sky and then adjusting the eyepiece.

Ballistic Coefficient — Wikipedia notes that “the ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight.” Less air resistance equals less drag, and less drag means better performance from a “body,” in this case, a bullet.

BC is denoted numerically, and the higher the BC number, the easier and more efficiently the bullet passes through the air. BC is determined by several factors, including the shape or design of the bullet, its weight and the diameter. The long-range shooter wants a high BC bullet to retain speed longer, drop less, and be less affected by wind.

For example, the Hornady ELD Match round in 6.5 Creedmoor, loaded with Hornady’s sleek, 140-grain bullet, has a very high BC rated at .646. Meantime, the Hornady 30-30 Interlock American Whitetail hunting round, loaded with a round-nose 150-grain bullet, has a BC of .186.

Muzzle velocities of these two rounds are different, but in general, the high BC ELD Match bullet cuts through the air much more easily than the rounded 30-30 projectile. Guess which one is the better choice for banging steel at 1,000 yards?

Cartridge Load — Long-range shooters use a variety of calibers, and within each caliber, there are many, many loads available. And each specific Cartridge Load has its own unique bullet weight, BC, and muzzle velocity. 

So how do you know which Cartridge Loads might be best for your particular long-range endeavors? Of course, one could buy thousands of dollars worth of ammunition, shoot it all and come to a decision that way.

But the smart shooter will save time and money by using Ballistic and its huge Load Library, which encompasses data on over 5,000 projectiles, factory loads, and military loads, plus performance data points (like BC’s) from leading manufacturers, military testing, and performance testing.

Using Ballistic, plug in the various Cartridge Loads you are considering, the distances they will be used, and the anticipated environmental conditions. Ballistic will calculate all the data needed to make the best load choice.

The Ballistic Load Library is updated quarterly, and the Ballistic staff is always searching for all that is new and improved in the world of long-range shooting, competition, and hunting. If a new factory round hits the market, for example, you can bet Ballistic will soon add it to the Load Library. 

Ballistic is definitely the place to go for ballistic information on the newest and the best bullets available if you are a reloader. Recently, Ballistic added the Sierra TMK or Tipped Match King to the Load Library. Sierra’s newest addition to their Match King line of bullets, the TMK features an acetal resin tip to reduce drag.

There’s so much more for long-range shooters to learn. But with Ballistic and some basic terminology as a foundation, the long-range world is an open and inviting place!

Ballistic is the definitive ballistics trajectory calculator, intended for long-range and precision shooters who want a serious–and a seriously accurate–application. Ballistic will calculate your bullet’s trajectory, windage, velocity, energy, lead, and flight time for any valid range. The app can also compensate for atmospheric conditions such as temperature, barometric pressure, humidity, and altitude–it can even accept density of air or density altitude inputs! The world-renowned JBM Ballistics engine powers all Ballistic computations. Ballistic is used by competition shooters, long-range hunters, and the military to deliver the most precise calculations possible.

With Ballistic, you’ll be able to make the most accurate calculations for every shot, everywhere, even in areas with no cellular coverage.

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