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internal vs. external ballistics

nemesisenforcernemesisenforcer Member Posts: 10,513 ✭✭✭
What's the difference and why should I care?


  • Rocky RaabRocky Raab Member Posts: 13,190 ✭✭✭✭
    edited November -1
    Internal ballistics is the study of all events between primer ignition and muzzle exit of the bullet.

    External ballistics is the study of the flight of the bullet.

    One you didn't not mention or know about is Terminal ballistics, which is the study of bullet behavior at and within a target.
    I may be a bit crazy - but I didn't drive myself.
  • Alan RushingAlan Rushing Member Posts: 9,002 ✭✭
    edited November -1
    "Internal vs. external ballistics . . ."

    quote:Originally posted by nemesisenforcer
    "What's the difference and why should I care?"

    Internal ballistics from the moment the primer is struck until the bullet exits the muzzle of the barrel.

    One should care so that the projectile exits the barrel without blowing off one's parts.

    External ballistics what happens to the projectile and the target once it has reached out and touched it.

    One should care so as to have some idea what is happening on the other end of things ... as in the receiving end.

    Why you should care? I have no idea. [:(] [;)]

    Maybe you could help us with that.[?] [;)]

    Perhaps so one would have some idea if the package and the delivery would suffice for the purposes intended? [:0] [;)] [:)]
  • sandwarriorsandwarrior Member Posts: 5,453 ✭✭✭
    edited November -1

    You amaze me at times with the "attitude". Why should you care????...because you reload that's why. And you need to know what you are doing and approximate values so as not to damage your rifle or yourself. And, know where your bullet is hitting. I don't know how many questions I've seen answered here for you by numerous members who "care". They "care" that you get the information you want and not blow your face off at the same time. Many people here have done the same for me.

    To answer your question it's as stated above. Internal is what happens inside the bullet during firing up to the point the bullet leaves the barrel. And, external is what happens when the bullet is flying downrange. Again, because someone "cared" to give you a better answer than your vague question allowed for, you now have how the third critical factor, terminal ballistics, plays into this.

    So you know that I "care", I'll give you more than you asked for as well. Internal ballistics is the whole background we do load development against. We want to know pressures during times of where the bullet is in a gun and what happens. It's even more important when working with semi-auto guns. Too much blowback and the slide slams against the frame. This will eventually break it. Not enough and the action won't cycle. Too much gas down the barrel at the port with cause an action to open prematurely or slam it back too hard.

    As far as the study of external ballistics it's whats allowed us to stretch out our distances of shooting accurately. It tells us that even though a bullet may be great for terminal ballistics, out of this particular firearm it won't stabilize. Because the twist is wrong. In the past we found there is a perfect twist rate for each bullet. And that some types of rifling are more effective. And, with newer and better tolerances we found we could 'over-rotate' a bullet and still have it be very accurate.

    Combining these attributes is what allows the 7mm-08 firing 168 gr. bullets to remain supersonic out to one mile in the high desert heat. And therefore quite accurate.

    And as RR said, terminal ballistics is important. Because often times the paper-punching, gong ringing bullets aren't the best choice for punching the right hole in a deer or an elk.

    That's why it's important and you should "care"
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