Yes the Little Torch will melt hard silver solder - I do it all the time with mine.
Silver needs a temperature of just under 2000 F to melt. Hard solder needs just under 1400 F to melt.
And according to the company's Web site, the Little Torch, using propane with oxygen, can create a 4800 F flame.
So I'm guessing that the problem isn't the flame being too cool, but rather the piece of metal that you're trying to heat being too large. Silver's a poor conductor of heat, so you can use a lot of flame warming up a piece to soldering temperature.
Either use a larger torch, two smaller torches at once, or create what I call a "soldering cave" using charcoal blocks.
To make one, prop two blocks upright on your soldering surface, forming a corner. (You can place a third block on top like a roof, but that may not be necessary.) Place your piece to be soldered in the "cave" and heat it with your torch. The blocks will hold and reflect back much of the torch's heat and make soldering much easier (or possible in your case).
Also, keep in mind that the hottest part of the flame is the portion just past the inner blue cone. If you haven't already checked it out, I point out this part of the flame in our video on lighting and using an oxygen/propane torch.
Best of luck!
~Addie~