I was under the opion that they all did

Who makes a quality nickels to dimes.

I know you already solved your problem, but wanted to reveal why this can happen:

If you insert the shell without a nickle on top, there is no "weight" to it and it becomes difficult to bang out, although you can do so with just the bang ring by using extra force and a very hard surface.

Otherwise, the shell is inserted upside down and you can see shiny side facing out (instead of the brass inside). The cup method mentioned before works, but I find an easier method is to stack two bang rings on top of each other - then you can bang it out with a little extra force as above.

-JoeJoe

It is a nice trick and I am told it was developed by Walter Gibson, who is one of my favorite magic writers.

Wife and I have been together 8+ years and the first trick I showed her was nickels to dimes. I used a TT(loaded with my nickels) and borrowed her nickels placing them inside a small cloth bag. Pretending to forget to have her write down the dates of each nickel, I poured the nickels from the bag (TT) and she wrote down the dates of each nickel. When I turned the nickels into dimes, of course each dime carried the same date as her nickels. To this day she BEGS for me to tell her how I did it and I love hearing her tell the story to her friends!