Several years ago I put together a scoped Tracker II (back when you had to drill and tap them yourself) for deer hunting. Indiana changed it's laws two years ago to allow pistol caliber rifles, which I much prefer so the Tracker II has languished in the gunsafe ever since.
I got the idea to make my wife a 'point and click interface' home defense weapon, and this seemed to be an ideal starting point.
I shopped the classified ads here at Greybeard and found a 20 gauge barrel for an excellent price and went to work.
I measured a generous 18 1/2" from the breechface and marked a line, matched the factory setback and drilled and tapped a 6-48 hole for a bead, then broke out the hacksaw, files and stones.
Here's the finished product.
The amazing thing is I just got back from the range, and in the process of testing it I wanted to see how well it fired slugs. I stepped back about 30 yards and fired two off hand, with just the oversized bead for reference. The two slugs were 1 1/2" center to center 1" from the X. I'll take that any day of the week.