In this little debate, I feel like I've been in the "I don't think the .410 is a terrible idea, but I'll stick with my 12 gauge" camp.
But trying to be objective about it, I toyed around with some of the numbers. The purpose isn't necessarily to compare it directly to a 12 gauge, but rather to think of the .410's merits in their own right. I'm basing it all on the Winchester load jmortimer linked.
First off, I wanted to know how much a 000 buck ball weighed (they don't put that information on buckshot boxes after all). I don't have 000 balls laying around, so I figured it mathematically. A standard 000 ball should be .36" in diameter, which would yield a volume around .400cc. Multiplied by the standard density of lead and then converting to grains puts us right at 70 grains per pellet.
At the listed velocity of 1135 fps, each pellet would have 200 ft/lbs of energy.
*I believe jmortimer cited 900 or 800 total, which would actually put each pellet at 160-180 ft/lbs. Maybe those were based on the energy farther down range. Or maybe the actual velocity is less than stated on the box. Or maybe the balls aren't quite 70 grains.
Whatever the case, for comparison, an 95-grain .380acp bullet at 955 fps has 192 ft/lbs of energy.
To be clear, I'm NOT saying that the .410 Winchester load is like hitting a target with five .380acp bullets at once. The 70 grain balls have a smaller diameter, less momentum, poorer sectional density, and NO type of bullet design. A true bullet can be designed for a desired balance of penetration and expansion, to destroy or disrupt an optimal amount of tissue and dump all its energy into a target. A spherical projectile can't really be tweaked to optimize the damage it causes.
Nonetheless, 160-200 ft/lbs of energy per ball is a significant amount, and maybe we could say shooting the .410 000 load is a little like shooting a target with five LRN .380 bullets.
I haven't seen anyone's results from patterning the .410 000 load, but from what I've read/heard, the patterns get ugly by 20 yards, but I've seen claims of 4" patterns at 7 yards out of a long gun, which is probably good enough for HD purposes.
Moving on, I was curious about how recoil would really come out (mathematically). I decided to check out Federal's 00 (9 pellet) reduced recoil 12 gauge load while I was at it. (I chose the reduced recoil version because its velocity is very similar to the .410 Winchester load)
- The weight of shot from the .410 load is about 350 grains. Weight of shot from the 12 gauge load is about 492 grains.
- I don't know the exact amount of powder used, but based on comparable reloading data, I estimated the .410 uses 15 grains of powder while the 12 gauge uses 25 grains.
- Velocities: 1135 fps for the .410; 1145 fps for the 12 gauge.
- For gun weight, I used Mossberg 500 specs: 6 pounds for the .410; 7.5 pounds for the 12 gauge.
Based on those figures entered into the Handloads.com recoil calculator, the .410 load showed 11.04 ft/lbs of free recoil, while the 12 gauge showed 18.59 ft/lbs of free recoil. In this case, the .410 has about 60% as much recoil as the 12-gauge.
It is worth noting, however, that many gas-operated 12-gauge may reduce felt recoil by about a third, which would make the perceived kick of the reduced recoil 12-gauge load similar to the Winchester .410 load while still throwing 40% more lead at the target. (Semi-auto .410s aren't much of an option)
In the end, my opinions are still about the same. I don't think the .410 is a terrible idea, but I'll stick with my 12 gauge ...not because I think I'm a big tough guy, but because I'm very familiar with it and prefer the greater number of projectiles per shot (ideally, 15 pellets of #1). Plus I have a recoil reducing stock that negates much of that issue.
However, for anyone wanting wanting something lighter, quieter, and softer kicking, the .410 with Winchester 000 ammo seems like a legit option.