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There are all kinds of ways to look at ballistics. One we don’t read about as often is kinetic energy. Kinetic energy is the amount of energy an object retains while in motion. For example, while a bullet is in flight. As a bullet’s velocity reduces during its flight, it loses kinetic energy.

Kinetic energy is not difficult to calculate since the formula is (½ X (mass X speed2)), i.e, 1/2 the product of bullet mass and the square of bullet velocity. You can use bullet grains for mass and then bullet velocity at different distances is easy to retrieve online, for example using Hornady’s standard ballistics calculator (https://www.hornady.com/team-hornady/ballistic-calculators/#!/standard).

Where all this gets interesting is to compare various cartridges/bullets at different distances to see what kind of kinetic energy loss they experience. Shown below is a table to exhibit some quick comparisons of kinetic energy loss at 200 yards.

Notice that, as one might expect, the 6.5 PRC firing a Hornady 143-grain ELD-X bullet retains kinetic energy quite well at 200 yards with just an 18.4% loss. The venerable 7mm Rem Mag is also impressive, experiencing just 19.2% loss using a Berger VLD 168-grain hunting bullet. No wonder the 7mm Rem Mag is such a popular hunting round. Also no slouch, the 300 Win Mag using 180-grain Nosler AccuBond likewise retains plenty of kinetic energy at 200 yards.
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it is pretty fascinating what starts happening with different bullets at different velocites and weights down range, even within the same caliber.

I got hooked on 5.56 ballistics for a while while building my ar pistol.
what happens at the muzzle and what happens down rage( say out past 200 yards) can vary drastically with different bullet weights.

like 50 grain will look really impressive based off muzzle data. but go 2-300 yards down range and that little pill just doesn't have the oomph it used to.

the opposite is true for heavier loads like the 77gr, a bit of a slouch at the muzzle comparatively, but its carries that energy much farther.
 
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