I don't understand the question. Rubber Batons for the most part are non-lethal unless you hit the bad guy in the head or directly in the heart, then they may be lethal. Nine or ten rounds of .22lr to the chest have a pretty good chance of killing on the receiving end. You are comparing apples to oranges. My Beehive round keeps a tight group (6" circle) at about 25' or 30'. The most accurate Beehive is one that has steel rifled sleeves or barrels. The aluminum Beehives that just have bored chambers are very innaccurate. Mine is a 9 rounder made by Randy Shivak.
Max effective range for a 22 beehive would be comparable to a 22 pistol with a 5" barrel. It would make a decent home defense round, where over penetration would be a concern. I'd say 20-30 yards max with the beehive. (Perhaps why the military never adopted them.) It is a very cool round to shoot, as well as the baton rounds. The batons however, don't penetrate (
) so, their effectiveness is limited to knock-down. They, however, are called "less lethal" for a reason. A baton round to the head, at close range, could kill someone, or cause serious injury. Perhaps a better, and cheaper round for your home defense 40mm might be the 40/12 or 40/410ga adapters on the market today. They will serve the same purpose as a short barreled shotgun, for home defense.
My .02c GROG
I know a good shoot is a good shoot, but if it comes out that you shot a guy with your evil "grenade launcher" instead of the camo shotgun leaning in the corner of the closet, it might not look too good....
Plus a 12ga with 6+ rounds of 00B/1B is going to be more effective and much quicker on follow-ups...
I am not aware of an adapter that will fire multiple shotgun shells, but space would be very limited in such an adapter. I do have a 10ga adapter that works rather well. (See video).
As far as home defense, there are plenty of better choices for home defense than a 40mm. I myself have two 40mm, and my home defense set-up is a Beowulf with grip-pod and laser for night time action. I have no close neighbors, so over-penetration is not a problem.