The smoke isn’t unusual. If you look at the bigger picture on Flickr, you can see it is ported on both sides and you can also see some smoke from the camera facing side too. It is kind of deceptive because of the color of the barrel and the smoke is darker right when it leaves.
One guy at the range was SO cheap, I think he reloaded his shell with 1/2 horsechit and turkey feathers, and even his didn't have that much smoke. Sorry, I don't buy it.
Notice how the smoke just wafts up and dissipates? There is no velocity to the smoke. Fake it is.