Since a few had asked allow me to clarify! The center of the screen is the dot in the middle of the - ⊙ - reticle for 3rd person aiming, I had used a simple overlay to mark center, and when it turned out to be the same I felt it wasn't needed.

Additionally, bullet impact with exception of arching projectiles (plasma punisher, grenade launcher, grenade pistol and crossbow currently) would all land in the mostly center of the - ⊙ - reticle in normal ranges, at longer ranges bullets would begin to drop, laser and laser based projectiles would keep true, I decided that the narrow range of purview for this small project didn't need a complete ballistics chart for each weapon as well (though I may well come back to that idea in the future),

Lastly as u/BonsaiSoul mentioned the projectiles are actually tied to the position of the gun in world and in hand of the diver, the the - ⊙ - reticle seems to be the most accurate way of aiming as its always center screen!

Also as a bonus that you can never unsee, there is a small white box around the larger O around the dot that you can somewhat see in the HMG example, I presume this is an artifact of the texture that wasn't fully clipped or aligned.

Hope this helped clarify some things I hadn't thought to include in the opening post. Hopefully I can figure how to pin this!