Experience with Lee Slugs?

[patocazador]

I bought a Lee mold that casts 12 ga. slugs they refer to as "key" slugs. They have a hollow base reinforced by a plate bisecting the hollow cavity.They weigh exactly one ounce and are .685" in diameter. I had to discard the first dozen or so because the mold and lead wasn't hot enough. Then it started throwing beautiful castings. I was surprised they were so good due to that intersecting plate.

Can anyone give me a regimen for loading them? Do you use a lubed wad at the base or an overpowder wad topped by a lubed wad? Does the hollow base expand to completely seal the barrel upon firing it??  These are 100% lead.

Here is a photo of some with a .690" ball on each side for comparison. The .690 ball weighs 1 1/8 oz.  .. 1/8th oz. more than the slug.

 

[Spitfire1]

I'll start off with a load slightly lower than what you use for the balls , try them with and without the wads . Only testing will tell what they like.