00buck has only 9 balls in the load. It was developed and always has been intended as a means of making a smoothbore gun a large game tool at close range. Its use as a defense round is a side effect.
#5 shot had around 350 pellets in the load.
At 40 yards a full choke will place 70% of the pellets (about 280) in a 30"circle giving around one pellet for every 3 square inches of target space. 2-3 of those #5 pellets will kill rabbit or any other small game.
I also keep a lot of #8 loads for shooting clays.
I prefer single 0 buck of .30 caliber (gives me a couple of extra balls per shell) for large targets and use it with a "super full choke" which we refer too as a "turkey choke" or "coyote choke." My turkey choke gives 100% pattern at 40 yards with most of the balls in a 18"circle. At 50yards I still have 90% with an occasional flyer outside the circle. Past 60 yards things start going (as you put it) pear shaped. The large shot is still deadly out to 70 or 100 yards, just not very predictable.
My general purpose shotgun sits by the back door right now with the turkey tube installed, one round of #5 as the first load up with single 0 buck filling the remainder of the magazine. Coyotes are my biggest concern but I want a round of #5 shot first up in case I see a rabbit or squirrel roaming the yard that needs to be eaten.
From my back door to the first fence is 40 yards and I have killed critters consistently inside that area. From the first fence to the second is the 100yard mark and I have killed a couple of coyotes half way across that range and helped a couple more find their overdrive gear as they neared the far fence.
I have a round ball mold for each of my shotgun gauges and they are very effective. I was not aware you fellows could own those on a shotgun certificate? Your standard certificate limiting you to shells with no fewer than 6 shot in the shell.
One can remove the shot from a shell, cast a ball and replace it into the shell. No need for fancy reloading equipment. I use a rifled choke tube for 4-6" groups at 100m. (I am sure you fellows are not allowed those) I can do the same with an improved cylinder (skeet) choke at 75m and can stay inside a 12" circle at 100m with the smoothbore and single round ball. Bear in mind that this particular shotgun has a scope mounted for assistance in shot placement.
One can also play tricks with the regular shot-shells and change their performance drastically....
Waxing the shells is something that takes on a few minutes work with a standard shell, makes it very effective against large targets, and if a situation returns to normal one could simply break down the shell and throw it away with TPTB none the wiser.
http://www.everydaynodaysoff.com/2011/07...gun-slugs/