Hello, I just purchased a Tristar 20 gauge magnum over/under shotgun. I was wondering if anyone had any experience with this gun and what choke to use. I have been looking at a carlson .555 and .565, and a primos tight wad in .570 constriction. The gun has 26" barrels. I would appreciate any input on these choke constrictions with this gun. I will be shooting lead and hevi shot loads. I was wondering if the .555 constriction would be too tight. As I get older the two 10 gauges I have are getting too heavy. This gun is really light weight at 6 lbs.