you take (rolling 1 die 50000 times), but how many dice you sum at each trial (rolling 2 die 50000 times). Though more dice give you a better chance of getting a good sample, rolling 1 dice will give you, on average, a straight horizonal line, where rolling 2 dice and summing them give you something like a bell curve but too high. Rolling more dice than that at a time give you something less like a bell curve (way to high), not more. Rolling 1.2 dice, as the OP states, gives you a distrobution more like a bell curve, no matter how many trials you take.