“Flat Shooting” Defined
Dr. John Woods 08.22.16
A so-called flat shooting cartridge might well just be in the eyes of the beholder. Still it is a concept often mentioned in discussions at firing ranges about a particular caliber or cartridge to demonstrate its ballistics, downrange flight pattern, and terminal effectiveness. Besides being hot around the campfires, this topic can really heat up some debates as well.
Conceptually “flat shooting” implies that the bullet from any particular round follows its flight path in as flat as a trajectory as possible. This also implies that the bullet should fly further because the bullet is not wasting flying time going through an arch path on the way to the target.
Flat shooing bullets are also presumed to fly flatter as the velocity increases. Thus, the invention and excited adaptation of the magnum cartridges such as the ever popular .300 Winchester Magnum. A bigger cartridge case holding more powder produces a greater span of velocities, and in turn the bullet flies flatter, delivering better downrange efficiencies. But how much better?
Let’s take a look at four popular and well researched big game cartridges. The .270 Winchester, the venerable time honored 30-06, the .300 Winchester Magnum, and the newer .300 Winchester Short Magnum, my own personal favorite. Do the magnums really deliver that much of a flatter shooting edge over these two popular non-magnums?
Comparing these four cartridges using basic standard bullet types and weights, the comparison here is for the .270 with a 130 grain bullet, the 30-06 using a 150 grain bullet, the .300 WM with a similar 150 grain bullet, and the .300 WSM also using a 150 grain bullet. Let’s inspect the downrange trajectories in inches at 100, 200, 300, and then 500 yards.
100 200 300 500
.270 1.2 -0- -5.7 -33.7
.30-06 1.4 -0- -6.4 -38.3
.300 WM 1.1 -0- -5.6 -33.4
.300 WSM 1.1 -0- -5.4 -32
From these factory catalog ballistics you can evaluate for yourself if the magnums do in fact yield that big of an advantage over the non-magnums. As you can see in reality there is very little difference even out to 300 yards.
The real practical difference would be of course in the terminal energy of each of these. At 300 yards these in order produce 1482, 1782, 2256, and 2316 foot pounds. In this regard the magnums excel, which is why they are magnums, as flat shooting or not.