From an old BruceZ
post:
<ul type="square">B = -(sigma^2/2u)ln(r)
r = exp(-2uB/sigma^2)
where u is your hourly rate
sigma is your hourly standard deviation
r is your desired risk of ruin
B is your bankroll[/list]You want to use the second formula. You SD is probably about 15 BB/100.
r = exp(-2*1*300/(15^2)) ~.0695 ~ 7%.