Under Armour

If you want a bigger return in the stock market, be prepared to take on more risk. But lucky investors in the right stock at the right time can score the ultimate disconnect: low risk and high reward.

Such stocks are not easy to find. There are just eight stocks in the Standard & Poors 500, including Micron Technology (MU). Facebook (FB) and Under Armour (UA). that have a beta over the past year of less than 1 that have also rocketed 75% or more over the past year.

Beta is a statistical measure used to measure how risky an individual stock is compared to the broad market. When a stock has a beta of less than one, like these stocks do, that means the stock has lower volatility compared to the market. Investors typically would expect to get a lower return when volatility is lower. But these eight stocks break that natural assumption, at least in the short run.

Consider the example of Micron Technology, which makes a variety of memory chips used in computers. The stock has a beta of 0.75 over the past year, S&P Capital IQ says, meaning its 25% less volatile than the stock market at large. But despite this impressively lower risk, Micron shares have soared 165% over the past year. Not bad, considering that the S&P 500 is up 17.7% during the same time.

Micron beats the S&P 500 (Chart source: MSN Money)

Facebook might be a member of one of the industries recently pinpointed by Federal Reserve Chairwoman Janet Yellen as being overvalued. But investors might be surprised that the social networking company has a one-year beta of 0.55, meaning its 0.45% less risky than the market. Meanwhile, the stocks gains have been astounding: up 162% over the past year.

Facebook tops S&P 500 (Chart source: MSN Money)

These low risk, high return stocks are certainly the exceptions, not the rule. There are 216 stocks in the S&P 500 with betas of less than 1. And these stocks, as youd expect, generated an average gain of 16.4% over the past year, lagging the markets gain.

And remember, too, academic studies show risk and reward are intermingled over the long run. Speculators might be simply taking advantage of short-term opportunities for big gains when the stocks are less volatile. Theres no guarantee these stocks will consider to have low volatility, high returns or either going forward.

S&P Capital IQ analysts arent all that positive on the the bunch. The research firm only awards two of of the eight stocks with its 4 rating, which is equivalent to a buy: Facebook and audio gear maker Harman International. Not a single stock gets the highest, 5, strong buy. And one of the stocks, Alcoa (AA). actually gets S&P Capital IQs lowest rating, 1, which is a sell.

Below are the eight low-risk S&P 500 stocks with big-time gains: