SHTF Firearms basics: Ballistics for beginners

\”Are YOU Ready?\”

I was hunting whitetailed deer a few years ago in Northern West Virginia. We’d seen lots of sign, and we knew the area well, where the deer were going. Most of WV is close, fast shooting through hardwood forests, so I selected a Remington 141 in .35 Remington to bring with me, a fast-cycling pump with great pointing characteristics. As an added bonus, I had a really hard time missing with its Lyman receiver sight. So, I hunted up and down some hills (they say after hunting WV for a while, one leg grows longer than the other because of all the hills), and made my way to a power line right-of-way, where my father was to meet me a bit later in the day. I was a bit early, so I decided to wait there at the right of way, a long swath cut through the trees for a high-tension power line. through you could see for probably a thousand yards, from the hill I was on , over a deep valley, to the crest of the next hill, I had to hope that a deer passed closer, within the 125 yard limit I’d set for myself with the pokey ballistics of the .35 I’d brought.

Soon enough, I saw, waaaaaay over on the facing hillside, a nice little buck come into the right of way opening and hunker down, in the open. I watched him through my binoculars, and wished my father would come soon, for he lugged around an old Remington .300 H&H mag with a 12 power scope, for this very reason. As soon as I thought that, I heard a twig break behind me, and lo and behold, my father stood there. I motioned him down to me, and showed him the deer on the hill.

“Geez son, I don’t think I want to try that shot, but you’re more than welcome to.” I took his rifle, and got into a sturdy sitting position, dialed the Leupold up to 12 power, and calmed myself, watching the deer through the scope. “I give it 500 yards, Dad, what do you think?

“All of that, I make it 600. That handloaded 180-grain bullet drops about 50 inches at that range.”

I mulled back and forth, not really wanting to take the shot on a deer laying down, since I couldn’t guarantee a clear shot at his vitals, and I didn’t want to wound the deer. Just then, the buck stood up, and turned broadside to me, making up my mind for me. “Holy crap, it’s suicidal!” Dad breathed to me while watching through my binos.  I looked at the foliage near the deer…it was still. No wind. Same near me. I knew a deer body is about 18-20″ deep, so I held the crosshairs about three feet over the deer, held my breath, and squeezed.

When I recovered from the recoil, I couldn’t see the deer in the scope. “Ahh, shit. Which way did the deer go?”

“It didn’t, son. It dropped where it stood!”

Sure enough, I looked closer, and I could make out the white underbelly of the buck on the hillside, so far away. When I (finally!) got to the deer, I saw that the 180-grain Speer bullet had gone right through the neck of the deer, killing it instantly. It never knew what had hit it. And let me just say…I’m glad I had a witness, because nobody would EVER believe I shot a deer at 600 yards.

I tell you this story, because without my father having done some research, and known his rifle, and known the ballistics, the only thing I could have done to shoot that deer would be guesstimating. Ballistics are key to know, if you want to try any type of distance shooting, and really, any type of shooting. Knowing how and why bullets act the way they do after you pull the trigger will give you a leg up on the competition, whatever it may be.

What are Ballistics?

Ballistics is, simply put, the study of a moving object, whether it be a bullet fired from a gun, a rock thrown through the air, a rocket going to the moon, or the Earth revolving around the sun. Obviously, for our purposes, we’ll be looking into bullets from a gun, specifically “external ballistics”, which is the bullet path from the time the bullet exits the muzzle to the time it impacts a target.

From the second the bullet leaves the muzzle of the gun, gravity starts taking effect on the bullet, pulling towards the earth in a parabolic curve called the “trajectory”.

Above is a graph showing the trajectory of a 180-grain bullet fired from a .30-06 rifle. You can see that, from left to right, as the bullet goes further away from the gun, it drops more. This is because the bullet is losing velocity, and succumbing more to the forces of gravity. This is a geometric function, and why it is a parabolic shape.  If this graph continued, you would see eventually a vertical line as the bullet loses all forward momentum, from air drag, and only moves downward from gravity.

Many things will effect how this parabolic trajectory looks. A longer, sleeker, more aerodynamic bullet will have less drag on it as it courses through the air, so the curve will be flatter for that type of bullet. A stumpy, broad bullet, like one found in a handgun, will have a shorter, more pronounced trajectory curve.

In the graph above, I used two extremes to show the difference in trajectory curves: A .220 Swift, firing a 40-grain varmint bullet at 4250 feet per second, versus a .44 Magnum rifle, firing a 240-grain bullet at 1760 feet per second. You can see how the much more aerodynamic and faster moving bullet has a much flatter trajectory, making it easier to hit with over much longer distances, since the bullet will not deviate as far from the aiming point.

Bullet weight also plays a major part in ballistics, one of which may be counter-intuitive. Yes, a heavier-weight bullet is effected by gravity more, but it also retains its velocity better at longer distances, thanks to a better ballistic coefficient. Ballistic coefficient is basically the ability for a bullet to travel through the air. A heavier bullet will be longer given the same bore diameter than a lighter bullet, and this in turn makes it more aerodynamic. Therefore, a heavier bullet with a similar profile will shoot flatter and resist wind better than a lighter bullet of the same diameter.

In the graph above, (I know it’s hard to see) but the upper, flatter trajectory is a 165-grain bullet fired at 2900 feet per second, and the lower one is a 130-grain bullet (both .30-06 caliber) fired at a faster 3100 feet per second. If the heavier bullet was fired at the same velocity as the lighter one, the differences would be even more drastic.

Wind drift is also a consideration, mostly with lighter bullets. It also is a parabolic curve, but not as pronounced. If, in my story above about the deer, there had been wind, I probably would not have taken the shot, for at those distances, wind drift (even a light breeze) would have pushed the bullet out of the envelope I was comfortable with.

So, to sum up this portion of (a very basic) ballistics study: knowing how the bullet acts after it leaves your muzzle will make you more adept at shooting, especially at long distances. So, be sure to look up the ballistic data on your firearm(s), know the bullet drop for your load, and you will be that much more effective.

If you’re using factory-loaded ammunition, most manufacturer’s websites have ballistic data for their ammunition, just a couple mouse-clicks away. Print the data off, and keep it with your firearm (some people even laminate it and tape it to the stock if they shoot at long distances often). The graphs I used above came from Gundata.org, which is a HUGELY helpful site if you wish to delve more into the mechanics of bullets and ballistics. Most common factory loads are listed by caliber.

If you handload your ammo, get with a buddy who has a chronograph, measure the average speed of your loads, and when you find the ballistic coefficient of your bullet (listed on manufacturer’s websites also), you can plug it in to the calculator above and get set up.

Above all, PRACTICE!!! This will help you know your limitations, how the gun works, how you and your load perform at long distances. The animal you shoot at 800 yards  and wound because you didn’t know your limitations does not deserve to suffer. Know your gun, know your load, know YOU. This could make all the difference in the world someday, when you are feeding your family and/or protecting yourself.

There is SO MUCH more to ballistics, but this should get you started…

Stay safe!

-TRW