London, Aug 3 :  Indian shooter Joydeep Karmakar finished a credible fourth in the men's 50 meters rifle prone event here Friday while Gagan Narang failed to qualify for the final.

Joydeep shot an overall score of 699.1, including 595 in the qualification and 104.1 in the medal round. His score in the final was third highest among the eight shooters.

Narang, who had won the bronze in the men's 10m rifle, finished a disappointing 18th.

Belarusian shooter Sergei Martynov kept a steady hand to take the gold by a dominant margin.

Martynov, twice a bronze medallist in the event, set a world record final score of 705.5 to win by 4.2 points after earlier equalling the world record in qualifying with a maximum score of 600.

Silver went to Belgium's Lionel Cox, who edged out Slovenian bronze medallist Rajmond Debevec by 0.2 points.

Ukraine's Artur Avvazyan, the gold medallist in Beijing four years ago, scored 593 in qualifying and missed out on the final, as did Australia's Warren Potent, who won bronze in 2008.

© IANS