Tuning Balistic coeficient vs. Reality

Jump to latest Follow Reply
Emu

Emu

Member
Jan 15, 2020
4,110
3,183
Queretaro, Mexico
First of all I need to recognize that I am not an expert.

Second, this is just a question.

Many of us have confirmed really good accuracy of our PCP'S flying the pellet at an initial speed of 810-850 fps. And better than above 930 fps.

Is this an aligned statement using ballistic coefficient or ballistic coefficient, then, is not an appropriate measure when applied to air rifles and pellets?


 
im not an expert either but in my understanding a faster pellet is more stable, has more energy and has a good trajectory ..to a point .. as 'mach' speed is approached it negatively affects the pellet flight .. so way i see it i like to keep all things about equal between guns and ammo as far as speed since all projectiles fall at the same rate at a given speed and around 900 is the sweet spot of best compromise all factots considered ... BC is on the minor end of of the important list outside competition imo ...
 
Upvote 0
The way i explain bc to those that aren’t in the know its the difference of driving a car that you have to keep your eyes on the road every second ( the pellet with a bc of .02 or less ) or driving a car having a snack and soda with your knee steering( slug with a bc of close to.1) the latter just tracks straighter and is less affected by outside forces ( wind)
 
Upvote 0
It is a piece of data for which I've never seen much value. Every combination of velocity, barrel twist rate, and projectile weight/length/shape has to be evaluated. Other things equal, a longer projectile of higher BC should hold up better at longer distances, provided you have the velocity and twist rate for stability. But, that number means nothing until it's tested. Most of us know, within a relatively narrow range, what weight and style slug or pellet we need for a given task. So, buy a bunch of stuff and head to the range. You're gonna end up there anyway.
 
Upvote 0
The way I think of it in a easy understandable way is this:

Because of the shape, pellets have a buble of turbulant air around it, as it moves forward. That bubble act as a sail for a crossvind, just like a sail on a boat. Cross wind push on the buble, and the buble will move the pellet which is inside it. The faster the pellet travel, the bigger that buble will be, because of more turbulent air. At a given speed the size of that buble will be so large that the cross wind will pull more than it would at a slower speed, where the buble is smaller. 

Myabe not scientific explenation, but in my mind it makes sence to me:)
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu