Simple explanation....What was not discussed is size of pellet, hardness of pellet, thickness of the walls on the wad, length of plastic wad, and speed at which shot is being propelled from shotshell….These factors all have influence on the pattern to which the choke has influence down range.
I am sure this was based on lead also. And not steel or hevi metals.
I am very sure this was based on factory loads and Sami specs.
But it gives a very good idea of
Choke types and estimated range.
Since steel(iron) will be less, and hevi
Metals will be more, plus like you said construction of the load.
Good read thou, and discussion starter. Lol