I would suggest that you do indeed get a shorter barrel. I would further suggest that it be a smoothbore one. If you feel like spending the money, Ghost Ring sights are nice, but for home defense, a bead will do.
Now for you load selections. In a patrol car, that 2-OO, 3-slug sounds fine, but for home defense it might be a bit much.
Many of us choose to load down at home, to #2 #4 or even #6 shot, for several reasons. I'll list a few main ones for my personally:
1. Effective range: The #2/4 buckshot will be effective inside your home, whereas it might not be as much so against humans at ranges that could be encountered by LEOs in an outdoor scenario.
2. Stopping effectiveness: 00 Buckshot and especially slugs will likely go right through someone at in-house ranges. I am a believer in the 100% transfer of energy theory, ie- that a bullet should stay in a body and not take any enrgy out the backside. I also subscribe to the "overload the nervous system" theory of what makes people stop. While a slug could well break the structure of a person, it requires relative accuracy to be effective. Meanwhile, a blast from #4 buck at close range is going to create the mother of all wound cavities (permanent and temporary) which is incredibly likely to stop your attacker, even without a perfect shot.
3. Overpenetration: This is especially important to those of us with kids or who live in apartment building or duplex. That Slug could easily travel through several rooms inside a house and even the outer walls and into the street or other homes. Similarly, the 00 buck will have no problem blasting through an interior wall (or two).
Suggestion: get a shorter barrel (and while you are at it, you could probably stand to lose an inch or so of the stock)with a cylinder or IC choke and a bead site. Before you head to the range, take some measurements in your home, look at the likely ranges you would be using the weapon at. Seriously, if you live in a 750 square foot house, why shoot at more than 12-15 feet?? Then play around with different loads at different ranges.
Fire slugs, 00, #4 (buck) and #6 at varying thicknesses of plywood (or drywall, if you can get some pieces) at the appropriate ranges to get an idea of the kind of penetration you are dealing with.
You might end up going with your original thought, youmight decide that #6 shot is plenty.
In the end, some ascending combination might still appeal to you, but you might start with birdshot instead of 00 buck.
[This message has been edited by Rob (edited 12-09-98).]