In a book titled 'My Olympic Journey', Karmakar recalls how he felt after reaching the final of the Men's 50m Rifle Prone before finishing a painful fourth.
"In London, my friend Vijay Kumar was on the podium. He had shot a sensational final to win India's second medal of the Games and the second silver medal for Indian shooting after Rajyavardhan Singh Rathore in 2004. Seeing Vijay on that podium, something inside me snapped. I started crying like a baby. At that moment, I realized what I had missed," recalls Karmakar in a book co-authored by journalists Digvijay Singh Deo and Amit Bose.
He claims he had a tough time in the lead up to the Olympics, thanks to Indian team's coaches Sunny Thomas and Stanislas Lapidus.
"Efforts were made to break me. I had to fight for my lawful place in the Indian shooting team for the 2012 Asian Championship in Doha, the last event before the selection committee for the Olympics met. I had not made the cut to represent the team in the actual competition in Doha, but had earned my right to shoot the minimum qualifying score (MQS), which is in accordance with shooting rules. For some reason, I wasn't part of that either, and I really had to fight and make representations to the NRAI to ensure the policy was followed," he writes.
"I had made it to the Olympic team, but support for me was missing on the ground. Harsh treatment was meted out to my fellow shooter Sanjeev Rajput and me. We felt like have-nots even though the sports ministry and the NRAI had backed the team to the hilt. The situation was getting more desperate with every passing day and it finally blew up in Munich during a World Cup.