I made these with some super bulky Reynolds Lopi that I bought a while ago (at half price) and hadn't found a use for. Because of it's weight I used it single stranded. I've felted the regular bulky Reynolds Lopi many times with great results and I thought I would get the same percent of shrinkage with this, but it looks like I was incorrect. They took about ten passes through the wash and one pass through the dryer to get them about as shrunken down as they're going to get and although made for a men's size 11 are more likely to fit a size 13 to 15. I didn't put much effort into shaping them while wet because I was disappointed about the size, but I think I still like the way they turned out, and they will make a nice present for my brother who's feet should fit in them perfectly. I just need to make another pair for his wife!
Here's before and after.