Dillon Arms

Doppler radar velocity measurement 
of coning bullet

Explanation of the oscillating nature of Doppler Radar velocity measurements

This drawing qualitatively explains the results of the Doppler radar velocity measurement for the 7.62 x 51 Nato bullet from its coning motion on the descending part of the trajectory.

While the coning bullet moves its tip towards the antenna, a velocity component subtracts from the radial velocity of the CG (the antenna "sees" an approaching bullet axis plus a withdrawing CG) and while the bulletīs tip withdraws from the antenna, a velocity component adds to the radial bullet velocity (the antenna "sees" a withdrawing bullet axis plus a withdrawing CG).

Thus, the oscillating nature of the measured velocity (see figure Go to figure) results from a superposition of the coning motion of the bulletīs longitudinal axis and the displacement of the CG along the trajectory.

To top of pageBack to textBack to main page