I edited, take a look
Can you please trust the Physics with Forensics student studying degree level Ballistics?
I can, but I like to discuss things

I was an academic at one point.
I know that all projectiles are arcing. The difference between bullets and projectiles is in velocity. With smaller velocities, you see the arcing effect faster. Bullets at their 800 m/s starts to arc noticably about 50 meters from the shooting point I guess. And bows/crossbows much sooner. The damage in turn is multiplication of velocity and bullet weigth (regardless, but not omitting the projectile shape)
What you want to achieve is to hit a specific point shooting from other specific point. You have two variables. An angle and the strength. With pistol or crossbow you may only change the angle. with bow or throwing weapons you have a possibility to change both. Since you cannot change the strength you can only hit a certain spot by shooting at exatly two angles - close to straight (at this range the angle would be around 1-3 degrees or shooting at a very high angle (with a distance less than 30 meters, you'd need to shoot at the angle close to 87-89 degrees). The second option while certainly viable will lead to projectile coming very high, fly for a long time (much longer than the three seconds we have in the combat turn) - you need to decelerate with the earth gravity to zero and then accelerate to the original speed. The problem with this approach (other then time) is the air resistance, taking out the overall energy of the projectile, effectively reducing the damage.
Noting the above, the usable approach is to shoot close to straight, using the minute moment of time when Stryker uncover the target.
or since you are planning to shoot just over the head of the Stryker that would be a called shot, wouldn't? and if you miss wouldn't there be a huge chance that if you actually hit Stryker instead of Ganger wouldn't you shoot at Stryker's head?
Right, wrong?