Ballistics, a great place to learn some basics



Experimenter P.O. Ackley is a fun read, you will find some of his books are still in print after many years, and they’re well worth your time. 

It was in hunting camp this year I decided to ask a question.. why? I guess I wanted to see what folks knew about gravity.

Here’s the question:

If you adjust the barrel of a rifle dead level, and you fire a bullet from that barrel, what information will you need to calculate the ‘flight time’ of that bullet?

assume the ground is flat… and that gravity here on earth is uniform.

Check all the information you need to calculate flight time.

  • The mass of the bullet.
  • The velocity of the bullet.
  • Air temperature
  • Distance from the barrel to the ground.
  • The ballistic coefficient of the bullet

Scroll down to the bottom to add your comments, there was only one guy in hunting camp who got this right, and as I mention elsewhere, it’s normally the Farm Boys that seem to know this stuff off the cuff. Yes, it was a Green Thumb from Tri Cities who grows tomatoes, peppers, and melons when he’s not trapping and counting bugs for the Agra Business.

Ballistics is a natural curiosity for the DIYer, it’s brain food, and helps you stay focused on reality. Whether it makes you shoot better or not, I don’t pretend to know..

George B.

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10 Responses to Ballistics, a great place to learn some basics

  1. Michael Lawton says:

    Distance from the barrel to the ground.

    A round fired from a level barrel will hit the ground the instant it would if it were dropped from the same height.

    Simple math…….

    Mike NJ

    • George B. says:

      What??? I had two guys at hunting camp bet me it was far more complicated than this! One owes me $10, the other $5 🙂
      As I often say… do the math before you invest.. If you follow the activities of the US Department of Energy… Solyndra and many others, you will certainly understand that they are making totally uneducated guesses as to where tax payers are FORCED to invest their money, and they ignore the same simple math that would prove the ventures a failure! the business plans literally defy gravity! There is only one other conclusion to draw if you reject this.. and that is corruption.

      Good Job Michael, we need to get you into politics, we need a man in there that knows the basics!


  2. Butch says:

    Dang, first guy gets it right before I had a chance, Oh well.

    Yessir, P.O. Ackley got it right most every time. There is a custom small ring 98 Mauser in 257 Ackely improved that was done in his shop standing in the corner within reach of me and a few boxes loaded with Hornaday 75 HP and Nosler 90 BTHP on the shelf. Owned it close to 40 years and still one of my favorites.

    • George B. says:

      Butch, the mention of the 257 cartridge reminds me of Ackley’s fascination with the Arisakas.. he put a lot of effort into his attempts to blow up that action, and called it one of the stronger ones he studied. too bad taking off the safety takes time and can be heard in the adjacent counties. I mention this because a lot of these were drug home by our Fathers in WWII and some rechambered for the 257×6.5MM, I own one, it was my dad’s.. ugly, but a good shooter.

      • Quinn says:


        You have good taste in guns as well as engines! My uncle was a SeeBee during WWII. At the end of the war he sent home all the stuff he could get his hands on (tools, mostly) including a crate marked simply, “GUNS.” One of the items inside was a Type 99 Arisaka (7.7 x 58) with the Imperial chrysanthemum intact and bayonet and scabbard. Codes stamped on the receiver indicate it was from 1944, before the Japanese started making the cheap “last ditch” Type 99s that are said to blow up from time to time. Chrome lined barrel, which I’m told was the first use of chrome in an infantry rifle. It’s supposed to be a nice shooter, similar to the .308, but it hasn’t been shot since about 1950.


        • George B. says:

          Quinn, glad you dropped in! Interesting about the chrome bore, seems it’s proven it’s value in the field, or at least a lot of people will pay the extra money to have it today. The Arisaka rifle I have is an early one with all the right marks, it’s been sporterized and a good rifle for a kid to carry deer hunting. The Ackley AI I have is the same 22-250 Ackley Sako Custom you saw at Magic, (the only custom built rifle I own). The cartridge to the left in the photo above is the 5.56 (.223).

          As for flight ‘distance’ out of a level barrel, it’s possible that the 22-250 AI could take top honors, with light bullets, full charges, and a loose twist, you ?might? make 4500 FPS. No doubt a smooth bore with a sabbot round would rule..

  3. JLB says:

    This was simple high-school physics (32 ft per second per second gravitational acceleration on earth’s surface / varies slightly from place to place dependent on density of underlying earth) – way back when!!!

    Regards, JLB

    • George B. says:

      JLB, there’s all kinds of hairs to split, some might even ask if the moon was directly overhead when the bullet was fired 🙂 The heart of the discussion in Hunitng Camp centered around the flight time of the fired bullet compared to the dropped bullet from the same height as the level barrel.

      In my mind, this is an example of a less complex problem where people typically view it more complex. Perhaps the more interesting fact is that people will even bet money it’s more complex!

      Had we collected opinions from all hunters on the hill, it’s possible that the popular vote would have been that the flight time of the fired bullet was longer.

      Now… if we turn our attention to Europe, and the EU, we might ask… is the problem there more complex than the one we discuss here?

      We could itemize at least a dozen irrational behaviors, but isn’t it as simple as spending far more money than they collectively make? But perhaps an even larger concern is North America is full of voters who think Europe is full of happy people dancing in the streets, working a short week, and getting at least a month vacation as an entitlement. Americans are busy watching realityTV, so little chance they’ll catch the news that Rome is burning today.

  4. Harold says:

    Hi George

    It’s amazing sometimes what you can pick up at a hunting lodge or shooting range from people who ought to know better. Your article inspired by P.O. Ackley reminds me of a recent visit to the brand new Rockcastle Shooting Range near where I live. On my first visit there before I had time to completely clear my pickup, my attention was taken by a golf cart heading “flat out” in my direction from a nearby skeet tournament in progress. It was only seconds until I realized I was its destination.

    The driver, an enthusiastic young man, wanted to know if I had any weapons and what my intentions were. I explained that it was my first visit and I had no weapons; just wanted to find out what they had to offer. That was his queue I guess. He launched into his apparently prepared spiel complete with a tour of the clubhouse, and a hand-full of brochures but no access to any of their several ranges.

    The last range he described for me was their 1,700 yard rifle range that he said was Barrett’s proving ground for their latest military offerings. He then proceeded to tell me about a rifleman he observed there who shot the head off a pin at the full 1,700 yards. “WOW” I said! “I’ll have to see that one!” Well, he replied it was a ball-point pin and he shot it with a with a bolt action .50 BMG necked down to a .223. I don’t remember Mr. Ackley ever writing about that one, and I suspect that if he ever tried it he wouldn’t have lived to write about it.


    How much of the information provided in your question would be required to calculate the velocity of the shrapnel generated from the .50 BMG / .223 wildcat chamber immediately on touching off the first round? I’m an avid reloader and I have no idea!

    Thought you and / or your readers might get a chuckle out of this one. I swear to you It did happen. It almost seems that some people just don’t know how far to push the hype anymore.

    Best to all


  5. Martinb says:

    You need the velocitie of the bullet and the distance front the barrel to the ground… I think is simple a hypothenus calculation… if you have the number, you can find the third one… (You can use this method only because you say that gravity is constant and ground is flat)… It’s what i think… 🙂

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