spaniel

I think the copper shotgun slugs are these Remington's and they are just a type 50 cal barnes like bullets in a sabot in the shotgun shell...

http://www.remington.com/products/am...bot-slugs.aspx

Copper. Tight-fitting, 8 fingered sabot. Centerfire round precision. Nose expands to over 2X cal. dia.. 5 rounds/box, 20 boxes/case

The 12 gauge Core-Lokt Ultra sabot bullet is a .50 caliber, 385 grain HP semi-spitzer. The catalog MV is 1900 fps and the 100 yard velocity is 1648 fps. The ME is given as 3086 ft. lbs. and the remaining energy at 100 yards is 2325 ft. lbs. The trajectory of that load looks like this: +1.8" at 50 yards, +2.4" at 100 yards, and +/- 0" at 150 yards.
The 20 gauge sabot bullet weighs 260 grains. It also has a MV of 1900 fps, and its velocity at 100 yards is given as 1615 fps. The ME is 2084 ft. lbs., and the remaining energy at 100 yards is 1506 ft. lbs. The trajectory of that load looks like this: +2.0" at 50 yards, +2.7" at 100 yards, and +/- 0" at 150 yards.