Static vs Dynamic BC for bullets

[wapiti13]

Check out the April Shooting Times article by Rick Jamison. He conducted a 30 cal test using a 300 WM to test book BC (static) versus the actual flight BC (dynamic)of very many bullets and weights. VERY INTERESTING results if his OEHLER IS CORRECT! Explains a lot of why paper trajectory charts do not match real world results. /ubbthreads/images/graemlins/shocked.gif

 

[Bart B]

It's nothing new that "paper" ballistics seldom match "real" ballistics. There's a few folks who have measured bullet's time of flight between two points as well as velocity at each one.

BC and drop numbers derived from these methods typically put the paper data to shame. Most folks don't realize that bullets have different BC's for different velocities which is why I think most published data just ain't quite correct.

 

[Michael Eichele]

[ QUOTE ]
BC and drop numbers derived from these methods typically put the paper data to shame. Most folks don't realize that bullets have different BC's for different velocities which is why I think most published data just ain't quite correct.



[/ QUOTE ]

Thats a fact!!

I have used some bullets and found them to be quite close to the published BC and other WAAAAAAAY off the mark. No pun intended.

Very true about differant BC's at differant veloities. They also can change with barrel twist, load density, barrel length and I am sure a whole lot more. I love the example of my 178 AMAX tests which out of an 11.25 twist 308 at 2550 FPS the REAL world BC was .318 on the G5 model and out of my 12x 300 RUM .495 on the G7 model which is VERY close to 1.015 on the G1 curve! Thats a HUGE differance.

There is more to BC's than most would think.