3" BB in a 12GA.18.5" barrel.

Would think it's probably as good as cheap 00 if not better.

Personally I wouldn't go smaller than #4 Buck unless I had no other options.

It's steel shot. It's going to lose it's energy far faster than anything lead because the shot is lighter in density. Also, there is the potential for stray pellets to ricochet off of hard objects even more so than lead. The wad cups are designed to spread the pattern unlike buckshot wads that are designed to keep it together. Take a pattern board out to 15 and 20 yards and see what happens. IMHO this is not a good option.

Don't get me wrong, I wouldn't want to be shot with it or anything else for that matter. It beats throwing rocks, but still not a good option.

I had steel come back at me as I shot a low flying duck.  Duck passed infront of a bridge support (concrete and steel)     that shit bounced off it like a superball.  
Also shot @ a duck that had a rockwall in the backround. Maybe 50-60yds out. I heard the shot rippin over my head in the canopy.  

If Its all I had I'd use it. But it's got alot going against it. Muzzle blast and recoil being one.  And it's steel. Steel sucks at killin shit.    
If I specifically wanted a waterfowl load for SD I'd look at the loads with TSS (tungsten )  I witnessed my BIL hammer a goose @ 90yds.  And it wasn't a single magic pellet kill either.

Would look on ammoseek for some buckshot if you're able to have ammo shipped to you. They've a few options there, though none are terribly affordable compared to what it once was.  It's the buckshot-pocalypse right now it seems.

The Canadian that talks funny patterned it out of several guns and shot it in gel....

https://www.youtube.com/watch?v=CKteNMB69sU

While I don't think it would be an ideal home defense round, in a pinch you and Mr. Badguy will be surprised!

Remington made a duplex Home Defense load a few years back that was made out of heavier than lead, Hevi-shot (near the hardness of steel).  It was 2 and 4 shot.  Dense patterns, big holes at close ranges.  I got some on clearance and it worked wonders on ducks at 40 yards and less.

Steel and non-toxic shot are very different from lead

Ya that's mainly it. I stocked up on rifle and some pistol ammo and completely forgot about shotgun.

Plus I thought the black cloud used the flight control wad to help with pattern. The most I'd shoot in my house would be 25yrds. I can't see how it could do much worse than some of the cheap buckshot patterns I've seen reviewed. And aren't the black pellets in BC designed to cut/penetrate?

My first choice would be federal 00 with the flitecontrol, but for $1+ a round I think I'll wait and stock up later. I'll probably check out the tungsten and some others and see which might be better.

Have u thought about making wax slug loads or recasting birdshot into buckshot?

I was thinking this.  I saw a video a while back that someone opened up a birdshot shotshell, poured in wax so that the shot did not disperse or diverge.  While the shot held together, I don't recall what groups  looked like. In a pinch that might work.  But there is also the argument that using birdshot, while possibly not lethal, will cause a tremendous amount of pain.  Wide patterns with significant tissue damage might make someone think twice. While not my preferred ammunition choice, I'd be glad just to have ammo and a gun.  There is a picture of someone who was shot with birdshot, at near point blank range, that resulted in a huge cavity in his chest.  

Call up your local high volume gunshops.  I have at least 2 gunshops that see a lot of volume in ammo and gun sales.  I went today to pick up my Tac14 and to see if they had #7.5 or #8, since my inventory was used up my last shotgun trip earlier in the year. While they only had #6, I found out they had some Remington low recoil 00Buckshot and Fiocchi Rifled slugs.  There was a 2 box limit on buckshot and slug rounds.

Lucky Gunner has some Aguila Rifled Slug Minishells.  I picked up some for an old single barrel break action that I am weary of firing full power loads through.  Not all pump shotguns can cycle these, but I am only planning to use them in a single shot shotgun.  They do have PMC low velocity #4buck 2 3/4, Winchester #4Buck Magnum 3 1/2", and case quantity Hornady Rifled Slug shells (100rnds for $160).

+1

But I will go even further.  If the only choice I had was between #4 buck in a 2 3/4" 12 gauge, or #3 buck in a 2 3/4" 20 gauge, I would probably go with the 20.

It is a shame that #2 buck is not more popular.

steel shot doesn't have the energy.
i'd rather have a dose of #2 lead shot.

lead or TSS.

Yea, but it's going to lose velocity fast as the range increases.
Judging by the number of people that load their guns for the "longest shot possible INSIDE my house" it might be just fine in a pinch.
I know people who clock coyotes at pretty long (shotgun) range with some of the BB loads but if for some bizarre reason I ran out of 00, then I'm just going to slugs.
But I step OUTSIDE with a 12 ga. regularly and some of the irritant critters can get much bigger than a coyote.

That's because previous panics were from gun-owner-types driven by concerns about impending gun control legislation.

This panic is largely from non-gun-owner-types driven by concerns that the coronavirus will cause civil unrest and a breakdown of society.

Yes, but I can't find any flitecontrol wads.

You won't.  
But regular buck is better than no buck. And at HD ranges does it really matter all that much?

I would like to see some balistic gel test on the bigger T BB #2 Hevi-Shot. Its heavier than lead and hard as steel so it wont deform. For stuff up to coyote

Hell I would like to see bucksot made from it. With a flite control wad you may have 70-75 yard buckshot

Id rather buy black cloud. Cut out the wad to reuse with 00 than use steel shot.

I'd just drill out the center of the crimp, dump the shot. Add buckshot & buffer. Hotglue a waxed paper disk to close it all up.

This is why I like my shotguns to have choke tubes.   I can do this with trap loads (and did 6years ago for my 20ga)
I may not get flightcontrol level performance, but the patterns weren't bad at all. And I found trap loads all the time during the last "crisis"

$6 a shot? Fuk

We recently did some shotgun ammunition testing at my Agency that I participated in.

Bare gel, heavy clothing, laminated glass, wallboard etc....

We looked at #4 buck as well as 00 and slugs.

For self defense.... 00 buck Federal Flight Control or Slugs is the way to go.