I experienced the same thing as I started to make Argentium granules.
What was happening was that the snippets would start to melt, get a
little bit round, and then roll off the block before they’d been
heated long enough to become ball up into a true sphere.
My solution had three parts: lower the angle of the block, make the
wire from which I make my snippets into ribbon in the rolling mill
before snipping, and use enough flame so that it takes very little
time to ball up completely.
One word of warning on the “use enough flame” idea. If the granule
doesn’t start to roll off after it balls up, get the flame off fast
or you’ll cook your granule to crunchy blackness…Argentium or not!
Best of luck granulating!