I'd hazard a guess that your guess is wrong.
Did you read that reasonably-accurate article by any chance?
In keeping with what EEngr said, The Forensic Outreach Team make the point that;
If fired at an angle between 20 to 45 degrees or even more, then the bullet will travel farther with a greater probability of hitting something (or someone). The uninterrupted ballistic trajectory will make it far less likely to engage in a tumbling motion, and allow it to continue at a higher speed over terminal velocity.
For the sake of clarity allow me to amend my earlier statement to read,
If I had to hazard a guess I'd say that the projectile was descending
on an uninterrupted ballistic trajectory at the point of impact.