Does Oscar’s Grind work?

How Oscar’s Grind is played

1. Each series aims to finish exactly one unit ahead. Start at one unit.
2. After a loss, keep the same stake.
3. After a win, raise the stake by one unit, but never above what is needed to finish the series one unit up.
4. When the series reaches +1 unit, start a new series at one unit.

What 20,000 sessions show

Sessions that finished ahead were up $199.95 on average; sessions that finished behind were down $937.49. 28.3% of sessions ended because the next stake no longer fit the bankroll or the table limit.

Oscar’s Grind only raises stakes after wins, which makes it feel conservative. A series that starts badly can still run for hundreds of spins, with the stake creeping up each time a win arrives, while the series deficit grows.

The median session lasted 225 spins. The median longest losing run was 7 spins in a row (the worst of 20,000 was 21), and one session in ten put at least $145 on the table in a single spin.

European versus American wheel

The same 20,000 seeds, replayed on a double-zero wheel. The second zero roughly doubles the edge to $5.26 per $100 wagered. Measured return goes from −$2.67 to −$5.41 per $100, and the mean session from −$123 to −$281.

The code that produced these numbers

This Lua is the strategy as Engineer mode runs it, inside the same sandbox and kernel. A test in the repository replays it against the bulk generator on fixed seeds and fails the build if the two ever disagree by a single dollar.

-- Oscar’s Grind: aim for one unit of profit per series, raising the stake only after a win.
-- Session rules shared by every 0xroulette.com/systems page:
-- $5 unit, $500 table max, walk away at +$200, and stop the moment
-- the next stake can't be covered by the bankroll or the table limit.
local UNIT, TABLE_MAX, TARGET = 5, 500, 200

local stake, profit

local function reset() stake, profit = 1, 0 end

local function place(ctx)
  return { { type = "red", amount = UNIT * stake } }
end

local function settle(result)
  if result.net > 0 then
    profit = profit + stake
    if profit >= 1 then
      stake, profit = 1, 0
    else
      stake = math.min(stake + 1, 1 - profit)
    end
  else
    profit = profit - stake
  end
end

-- Shared wrapper: enforces the session rules around place/settle.
strategy = {}
local start, stopped

function strategy.setup(ctx)
  start, stopped = ctx.bankroll, false
  reset()
end

function strategy.bet(ctx)
  if stopped or ctx.bankroll >= start + TARGET then
    stopped = true
    return {}
  end
  local bets, stake = place(ctx), 0
  for _, b in ipairs(bets) do
    if b.amount > TABLE_MAX then stopped = true end
    stake = stake + b.amount
  end
  if stake > ctx.bankroll then stopped = true end
  if stopped then return {} end
  return bets
end

function strategy.on_spin(ctx, result)
  if not stopped then settle(result) end
end

Session rules

Limitations

One bankroll, one unit size, one table limit, and one walk-away target. A bigger bankroll or a higher limit moves where a progression breaks; it does not change the return per dollar wagered. Spins are fair and independent, as on a correctly functioning wheel or a certified RNG. Physical wheel bias is a separate question, covered on Physics.

Related

• Does the D’Alembert system work?
• Does the Labouchère system work?
• Does the Fibonacci roulette system work?
• All 20 systems, compared on the same seeds