Y’all are way to smart for me. I just run light 2 3/4 shells through my Parker or I stock up on RST shells at a shoot. If I’m shooting a non-Parker 16 ga with 2 1/2 chambers, I buy 2 1/2 shells. It’s pretty simple, but I’m a simple guy
Lengthening the chambers costs money, decreases the value and don’t do a dern thing for the shootin. Ain’t gonna do that.