Even with the grainy video I could tell it was a club! Who the hell holds a rifle or pistol like a baseball bat? Cops overreacting. I know there must be a training scenario for this.
With a no knock entry I could see ANYONE, even a drug dealer, reacting like that! Someone barging into your home like that, even the police yelling and screaming. It is called home invasion and the yelling is to SCARE you and CONFUSE you! Seems like he was just defending his home.
It is your home and I know my Saiga12 would have have been making happy flashes regardless who it was.