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Ummmm. Indeed they do but it is my understanding that they are to be used as a Sabot slug so no "falling" involved then. Used with the WAA 12 which is a perfect fit, they don't "fall" down the bore,...

Nope.
It seemd good odds that if the ingredients and instructions etc as named by the manufacturers were used and followed, then all should be tickety boo...So, brand new gun.... ended up firing...

Ummmmm. In the case of the Lee 1 ounce and the Lyman 525 gr, they both fit snugly into waa12 wad....so is the "bearing area " of which you speak, the base of the slug or?

Asking for a friend :>)

Ahhhhhhhhhhhhhhhh.

Your image tickled the little gray cells and I went searching and found i had a 100 pack of Lyman 520 gr 12gauge slugs. Just like the right hand ones in your image. AS I...

Um..... to be a little more precise, don't you mean inside a sabot? Which I think is now illegal