3 ways of finding muzzle velocity?

[bails24]

Homework Statement

I have been measuring the drop over varying distances of a projectile that was fired horizontally. I have measured the drop(s) of shot from the horizontal. while recording the distances to the target.

Homework Equations

I have been told to use s=ut+1/2at^2

The Attempt at a Solution

accelartion=gravity
s=1/2gt^2.
The suggested formula uses time, and i don't have the times recorded, is there a way round or do i need time?

 

[RTW69]

The distance of the horizontal barrel from the ground is s. Knowing s you can solve for the time, t for the bullet to hit the ground. The motion of the bullet in the vertical direction is completely independent to the horizontal motion of the bullet. The vertical motion is only influenced by gravity and is similar to just dropping the bullet from the height of the barrel from the ground.