I know I should pattern them and will when I get a chance.
But just wondering how will spreaders pattern out of a twelve gauge cylinder bore? I have a case of them from 10-15 years ago and thought I’d use them up on ruffed grouse.
From everything that I have read, spreader loads don't spread as much as the choke is opened up. I make spreader loads with X-Stream inserts from BPI and Spred-R inserts from Polywad. When I pattern tested the spreader loads, I confirmed, at least for myself, that spreader loads don't spread much in open chokes.