Thank you Stan. I hope your .410 is perfect. 16" at 32 yards is not slightly off! How can they sleep at night.

I had the IC and mod choke tubes in and had forgotten to take others. My shooting partners were waiting for me so I was a bit rushed and did not think of switching tubes. I just thought "darn, I should have brought the other tubes".

Before I do anything I will pattern it again with a different tubes.

Chuck, thanks. The sides are straight so it seems it is either the threads are off center or (I hope) something is wrong with the choke tube.

So many guns, so little time!