Roger,
Here are the pic's I mentioned in the pm.
Everyone else, these are pic's of a work base I make for use with my Lee Loaders. I use 1/2" steel plate and glue a piece of closed cell foam to the bottom and trim it to fit. This particular one shows two layers but that is not needed. It was a trial and error process and the first piece I used was some 1/4" red rubber used for gaskets. It did not do what I wanted it to do which was allow me to pound on my dies and not make a huge racket. I then added some 3/8" closed cell foam that feels about like a piece of wrestling mat only thinner. Now it works great. This one is about 7" by 6" but 5" by 6" is totally adequate.
I got the idea from watching a youtube video showing Dick Lee loading a round with his Lee Loader kit. I couldn't see what he used for a work base but it sounded like it might have been a slab of steel. Well, one thing led to another and this is what I ended up with. I like it a lot and it works quite well. I can sit and load at the kitchen table and not make a huge racket.
The black foam rubber I used was some scrap piece I got from an estate sale but I am sure that there is a very easy and common alternative. That would be one of the cheap neoprene "beer can cozy's" that you can buy for about a buck at most department stores. Just cut it open, roll it out flat, coat both the rubber and the steel with contact cement, let it tack and stick together. Trim the edges and you're good to go. Just keep the size of your steel plate small enough to not overhang the edges OR cut the can cozy into strips and glue it on like a border and it would work just as well. A scrap piece from a thin ethafoam camping pad would probably work well too.