Posted on 09/27/2018 5:40:09 AM PDT by w1n1
Calculate the RPM of a bullet coming out of a barrel for a big surprise.
There are many factors involved like ballistic coefficient, size of projectile, speed of projectile, weight of projectile, etc.
For instance, round ball rifles need a slow twist for maximum accuracy while mini- ball rifles need a faster twist and modern smokeless powder needs faster twists.
They even fool around with types of rifling and things like gain twists.
The complexity makes it interesting.
For simplicity, stick with a 1:7 rifling twist. That’s his conclusion? Meh...I just came for the grammatical errors.
And calculate the energy due to the spin
Faster twists use heavier bullets in that particular caliber.
Anyone who has thrown a football should understand some of the basics of spin stabilization. Not enough spin for the weight and speed makes the football wobble or go end over end. Too much spin and the ball won’t follow the leading point in its flight. Instead, it will remain at whatever angle, in reference to the ground, it began with througout its flight.
If you want complexity, consider the cartridge shape, volume, amount of powder, burn rate of powder, etc to understand the combustion chamber effects created by those variables!
It is fascinating stuff!
If you want something to ponder, consider the Ackley Improved cartridges and the reason they generate higher velocities than their conventional root cartridges.
The short answer is that the 45 degree “shoulders” create a more efficient combustion chamber.
It is also known that the more full a cartridge is with powder, the better....providing you do not exceed safe pressures!
Extremely low volumes of powder to cartridge volume have been known to create extreme pressure situations including ruptured barrels!
Despite what I wrote, the science behind cartridge shape, volume, amount of powder, etc is not well understood.
The next real science is in this area as rifling, BC, etc are all well understood.
And calculate the energy due to the spin
I remember physics class where we were supposed to calculate the amount of heat generated when a bullet hit a block of wood. I never got that right.
Want even more surprises, calculate the RPM of a bullet coming out of a 16” and a 20” barrel, both with the same twist rate.
At extremes, compare a spiral football pass with a knuckleball.
Just looking at it from a physics standpoint, I’d say yes, but only at a distance that requires more energy that is diminished by the amount of energy in the spin rate................
Brady Vs. Kaepernick.......................
That'd be spiral vs. knucklehead...
Exactly. Also a ball with too much spin descends with the leading point too high. The ball should follow the point.
LOL!............yes!...................
W1N1 daily trivia,
Just get a rifle that shoots 1 mile with accuracy.
Last weekend I spoke with my nephew's father in law who is retired and moved to mid Michigan and took up competitive bench rest shooting.
I was amazed at how complex the competition level is, especially when it comes to powder charges, shell casings, and tons of other stuff.
Fortunately for him, where he shoots there are several old timers who have been national champions and they have taken him under their wing and have been mentoring him........
Well, they're learnin'. A bit slow, but learnin'.
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