Tools not correctly being welded to a custom rig?

So I have a custom rig in my game, and I'm trying to get this gun working but the tool itself is not welding the the character...

Character: https://gyazo.com/2dc016fb632136702f0117d8e9df8561

Problem: https://gyazo.com/e1ef7172771ca5a3c87f5bb73af7ac06

I've tried pasting an invisible R6 rig over the character, that didn't work, and I've even tried making my own weld script

local Player = game:GetService("Players")
local Char = Player.LocalPlayer.Character

local tool = script.Parent.Parent

tool.Activated:Connect(function()
    local weld = Instance.new("Weld")
    weld.Parent = Char
    weld.Part0 = Char.RightHand
    weld.Part1 = tool.Handle
    print("Welded")
end)

The problem seems to be that the tool is not detecting when its activated.

The humanoid type is set to R6, when I try R15 the character picks it up, but clips into the ground and gets launched.

I've tried everything I can think of but nothing works!