BodyForce applied to object in the wrong direction?

Hi, I'm trying to make a script that throws a ball in the direction the player clicked. What I have so far is

Local Script:

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()
local mousepos = mouse.Hit.p
local handle = script.Parent
local tool = handle.Parent

local RS = game:GetService("ReplicatedStorage")
local ThrowBallEvent = RS:WaitForChild("ThrowBall")

tool.Activated:connect(function()
    ThrowBallEvent:FireServer(tool, mousepos)   
    tool:Destroy()  
end)

Server Script:

local RS = game:GetService("ReplicatedStorage")
local ThrowBallEvent = RS:WaitForChild("ThrowBall")

local function ThrowBall(player, tool, mousepos)

    local ball = tool:clone()
    ball.Parent = game.Workspace

    local rootpart = player.Character:FindFirstChild("HumanoidRootPart")
    local humanoid = player.Character:FindFirstChild("Humanoid")
    local head = player.Character:FindFirstChild("Head")

    local newhandle = ball:WaitForChild("Handle")
    newhandle.Position = head.Position + head.CFrame.lookVector * 4
    newhandle.CanCollide = true

    local force = Instance.new("BodyForce", newhandle)
    local targetpos = mousepos
    local initialpos = rootpart.Position
    local direction = (mousepos - initialpos).unit
    force.Force = direction * 300

end

ThrowBallEvent.OnServerEvent:Connect(ThrowBall)

The ball is thrown, but the direction of the force is completely arbitrary. Sometimes the ball will take off to the left, sometimes it'll go behind me, and sometimes it'll go straight. Any idea on why it's acting like this and not just going where I click?