LOL!
"Chain shot" for a shotgun!
That's cool!
Here's a tip back for ya...
Most shotguns with factory ammo give you about 1" of spread for every 3 feet of distance.
Inside a house you ain't gonna get much spread with buckshot, bird shot, or any other factory ammo.
If you flatten the pellets slightly...just put a flat side on 'em with a hammer...you'll get better spread.
Another wicked load...AND DON'T DO THIS WITH A CHOKED BARREL!!!...is take the shot out and load the shell (12 gauge or larger ONLY) with a stack of dimes. Nasty!