NEW YORK -- Molson Coors(TAP) - Get Report has been stuck in a range, but traders are looking for a breakout. 

OptionMonster's Heat Seeker system detected the purchase of almost 15,000 May 77.50 calls Tuesday, most of which were priced for $2.45. About 16,000 April 77.50s were also sold for 85 cents in volume below previous open interest, so it appears that an existing long position was rolled forward. 

Long calls fix the level where investors can buy a stock, allowing them to profit from a rally while risking only a small fraction of the share price. Their cheap cost can also generate significant leverage on a percentage basis. Another advantage is that capital can be moved from one contract to another, as we saw Tuesday. 

Molson Coors's shares were down more than 1% when the unusual option activity began, rallied into positive territory, and then rolled over with the rest of the market. The stock ended the session down 0.37% to $74.45. 

The beer company has mostly remained between $70 and $78 since June. The next earnings release is due in early May, so Tuesday's call roll will let the investor benefit from a strong report. 

Tuesday's total option volume was 13 times greater than average in the name, with calls outnumbering puts by a bullish 21-to-1 ratio.

-- Written by David Russell of OptionMonster

Russell has no positions in TAP.