I am having trouble to get a Carcano fragment deflecting from far up on Elm making it to Tague.
Estimating a Ballistic Coefficient for a de-jacketed and deflected Carcano bullet off a hard surface was explored to see if a deflected and/or fragmented early shot could readily reach James Tague. The results were not very reassuring that this would happen from way up on Elm.
BC’s of deformed and fragmented Carcano bullets could not directly be found and were not listed in one reference that discussed degradation of ricocheted bullets, but BC’s of a few metal jacketed 9mm bullets that were shot at just over mach 1 to ricochet off a hard surface were measured and used here to estimate a BC for a ricocheted Carcano bullet. The 9mm bullets were deformed but did not fragment, so their mass of 115 grains remained close to what is estimated a de-jacketed Carcano would be at 125 grains.
Also, since the 9mm bullets were deformed but not fragmented, the average BC of the lower third of the BC’s reported on them was used to estimate a fragmented Carcano. The average of the lower third of the 9mm bullets tested was a BC of 0.006
Here was the issue. In conjunction with the above base assumptions, I used a rough estimate of Tague being about 150 yards (450 feet) ground distance from the traffic mast which was in front of the TSBD, and about 32 feet below it in elevation. A deflected and fragmented bullet would have lost most all of its aerodynamics and spin stabilization so would have randomly tumbled through air down the street with a lot of air resistance. To hit the Tague curb (and assume nothing else in-between) it would need to retain a high speed to make it down to the curb given its high air drag (very poor BC).
Assuming a ricochet off a mast that caused a loss of jacket and changed direction vertically up and laterally to the right, at the same time, and having the new direction being initially horizontal in a direction toward Tague, a trajectory estimate using the Shooters Calculator shows on its graph that roughly to get out to 150 yards at -32 feet fall, a core fragment would need a velocity of greater than Mach 3 (~3700 ft/sec) to make it down in that area of the curb for those conditions.
The input used in the Trajectory Calculator:
Drag Function: G1 (G function for standard bullets)
Ballistic Coefficient: 0.006 (BC estimated from poorer deformed 9mm ricochets)
Bullet weight: 125 grains (de-jacketed Carcano core)
Initial Velocity 3700 ft/sec (this was the input needed to make the graph get near a -32 ft fall at 150 yards out)
Zero range: 1 yard (set to 1 to create a horizontal initial trajectory)
Hopefully this link with the inputs populated works.
https://shooterscalculator.com/ballistic-trajectory-chart.php?pl=%5BPreset+Name%5D&presets=&df=G1&bc=.006&bw=125&vi=3700&zr=1&sh=0&sa=0&ws=0&wa=0&ssb=on&cr=180&ss=1&chartColumns=Range%7Eyd%60Elevation%7Ein%60Elevation%7EMOA%7EFBFFF5%60Elevation%7EMIL%60Windage%7Ein%60Windage%7EMOA%7EFBFFF5%60Windage%7EMIL%60Time%7Es%60Energy%7Eft.lbf%60Vel%5Bx%2By%5D%7Eft%2Fs&lbl=&submitst=+Create+Graph+
This probably calls for a more detailed review on the inputs, but a first check on this didn’t seem to pan out. If the implication is correct, it probably suggests the early first shot got disintegrated in a collision or deflected somewhere else not as far away as the curb down by Tague.