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Schreck5
09-19-2019, 06:58 PM
Does it take a heavy, fat boolit longer to stabilize in flight than a lighter, slimmer boolit? Please explain your answer. Is this what the ballistic coefficient is supposed to tell us?
EXAMPLE........ .454", 325 gr hoolit vs. .454", 225 gr boolit
" " " " " " " .311", 180 gr boolit

John McCorkle
09-19-2019, 07:08 PM
So alot of factors as I understand it and may not be as connected as you mentioned in your question.

Stability includes a few other factors, barrel twist and bullet length, also velocity...so variables start to add up on top of each other but any number of sites on ballistics can help peel apart the physics involved or books such as applied ballistics or understanding rifle ballistics give a good primer on the topic.

Ballistic coefficient is a different factor...it's an external ballistic factor of how well the bullet carries it's momentum against forces of friction...like a paper towel (example I like to use) same paper towel wadded up very loosely and thrown will not go but a foot or so before slowing because of all the friction with air....but ball that paper towel up very very tight and throw it with the same amount of force and it'll make it across the room....that in a nutshell is what ballistic coefficient is a measurement of. Shape, diameter, weight and design overall (where the centers of gravity are on the bullet) matter alot with bc. Again alot of physics involved but not specifically tied to how easily a particular bullet is stabilized. Two different categories with differing factors of measurements

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JBinMN
09-19-2019, 08:19 PM
Actual Page of the book, 271 at this link:
https://ia800205.us.archive.org/1/items/Handloaders_Manual_Naramore1943/Handloaders_Manual_Naramore1943.pdf

and subsequent pages... May help.

Is just one way that things are explained in what could be considered a "laymans" , or "average persons" language.

I was recently reading this book & it came to mind again in a previous topic, but may also help here for some.

G'luck!
:)

megasupermagnum
09-19-2019, 08:22 PM
Bullets stabilize in the barrel, not the air.

Hick
09-19-2019, 09:56 PM
Spin is what stabilizes a bullet. How much spin it takes depends primarily on weight, length and diameter. How much spin you get depends on barrel twist and velocity. There are stability calculators available on the internet for this.

JonB_in_Glencoe
09-20-2019, 12:01 AM
As I see it, you are either gonna have stability, or you are not.
If you don't get the correct spin out of the barrel, the bullet will just become less stable as time passes.

I gotta ask, what is a "slimmer boolit"

fredj338
09-20-2019, 03:40 PM
As I see it, you are either gonna have stability, or you are not.
If you don't get the correct spin out of the barrel, the bullet will just become less stable as time passes.

I gotta ask, what is a "slimmer boolit"
^^^THIS^^
As bullets get heavier you need a faster twist or higher vel to get stability.

Schreck5
09-20-2019, 07:56 PM
Thanks JBin and John M for the references. It seems that all of the 'siences' are above my intelect, but I do find them fasinating.
Especially Physics. Bruce