I use the same slicer with a serrated blade. Two tips:
Cold or very cold meat slices much better than room temperature.
Don't push hard on the meat, let the slicer do the work.
Same here - I take used coals from my kettle. It would take quite a cook to go through more than a full ring of coals, though. I just did 40+ pounds of ham, bacon and beef over 14 hours on a cold and windy day without adding.