Silencing a 50 cal???
You can silence the blast of most weapons. But supersonic projectiles cannot be silenced as they produce a sonic boom.
Silencing a 50 cal isn’t all that difficult. Drill some holes in the barrel and slide your can over the holes then extend beyond the end of the barrel a suppressor to break the speed of the gasses exiting the barrel. That way the suppressor sticks out six inches instead of eighteen, twenty four or thirty six. Keep in mind the slower the gasses exit the suppressor, the more heat it will retain.