Agreed on the number 6's from the .410.

I used 6 shot 3" .410 loads for all of my shotgun work for a long time growing up, long after I had a 12ga of my own to use. Undoubtedly, the 3" .410 with 6's is the best running bunny medicine around.

One trick I used, which is a benefit with or without dogs, is to develop your ground with cover to favor rabbits. Build brush piles, allow lines/clumps of brush to grow, leave decent grass cover in certain areas, etc etc. I added a few brush piles to some of my pastures that we hunted rabbits in many years ago, and forever since they have been more productive for rabbit hunting.