I bought a double barrel 410 for my sister and cut it down to 18 and 1/2 inches. I put two 3 inch magum 000 BUCK in the chambers. Five 36 caliber pellets per barrel. So she gets a spray of TEN 36 caliber round balls flying out at 1200 fps in front of her with two quick pulls of the trigger (single select trigger).

Why?

Because she has mountain lion problems on her Alpaca Farm and she is small and cannot handle a bigger gun plus the 000 do not kick as much as slugs, yet the 000 are nearly as big as a 410 slug, and you have alot more of them.

I patterned the gun with these and it is a nice 8 inch circle with both barrels at 30 feet which is about what she would need the gun for.