ORIGINAL: mnbirddog
He was saying that the due to the arrow resting below the sight, the arrow will be at a somewhat upward angle. When it is fired, it initially has an upward velocity component. Gravity immediatly begins slowing that upward velocity, but it takes some time. So basically, he is saying gravity doesn't immediatly begin to decrease the distance from the arrows initial posistion to the ground. I don't have a clue what calculations people used to determine their numbers, and I'm no engineer so I wouldn't be able to calculate it myself either. However hornady's calculator shows that a 400 grain projectile at 300 fps and a 2" sight height with a 17 yd zero would be -2" at 0yds, 0" at 17yds, and -2.9" at 25yds.
Can anybody calculate the MPBR (+/-2") for a 400 grain projectile, 300/350 fps, and no drag (it isn't that much a factor at those velocities/distances anyway) and see what in an ideal condition an arrow could do?
I did, refer back a page. I came up with, in idea conditions, an arrow keeping in that 4" window out to 32 yards if it travels at
(corrected p 4) (if I remember right). It blew my mind too, but remember, no air resistance!
Weight has no influence on how fast an object drops. I came up with, using constant acc. equations that are standard, an upward velocity V(y) due to that slight upward tilt of the arrow of 5.7 fps to give it a max of 2" of height before the arrow starts falling. Transfer the numbers into the X direction using the same equations and away you go....