[Errant]

What's the pattern like at say 20 steps? :) The rifled barrel isn't going to give you much squirrel killing capability in a tall tree.

I make and shoot shot shells in my 45 colt revolvers. They're great for snakes at less than five steps but worthless after that. I figure the 410 down a rifled barrel isn't going to be much better, though I have no experience with one.

[Yosemitest]

Any shotgun is about barrel length.
At 20 paces the number 7 is probably about a 6 foot diameter on a long barrel, and on a three inch barrel, it's about 12 feet.
To do any damage with number 7 shot, you've got to be within 20 feet.