jimmyd is correct in saying that most SxS guns of our interest have the open choke in the right barrel and it is generally believed that when found to the contrary;i.e.,an open choke in the left barrel, the gun was ordered by a left handed shooter. BUT, as pointed out in an article in the Fall 2015 issue of the LCSCA Journal, some shooters including hunters preferred an open choke left barrel. We are so used to open choke right barrels that we think something is wrong when we find something different. As an example, in a recent post on the Parker forum there is a comment, "....the chokes are reversed on my Grade #1 hammer gun. The open choke is in the left barrel while the tight choke is in the right." The gun could very well have been ordered that way or subsequently modified to suit a right handed shooter as many of us prefer.