Overnight co-leader Ramsay fired a second successive five-under-par 66 for 10-under-par 132 at the Karnataka Golf Association course, which is hosting the approximately US$1.25 million Asian Tour event for the first time.
Thai duo Panuphol Pittayarat and Chapchai Nirat, who last won on the Asian Tour in India in 2009 where he set a new world 72-hole scoring record of 32-under-par 256, and Jaakko Makitalo of Finland returned with matching 68s to stay within touching distance of Ramsay.
Indian star Gaganjeet Bhullar, who won his fourth Asian Tour title in Macau last week, led the local charge with a round of 69 for tied sixth position and is five shots off the pace.
Ramsay, a two-time winner in Europe, made 11 consecutive pars after his early birdie on 11 but bounced back on his homeward nine with four birdies including a tricky 25 foot downhill birdie putt on the last.
"It is always nice to hole a birdie on the last. It makes your lunch taste a little nicer," smiled the 29-year-old. "The key was patience. I knew I was playing well and hit a lot of good iron shots. If you keep playing that way, sooner or later you will make something."
"It was a really nice way to finish. I stayed patient and you have to find the fairways and get good angles at the pins. I felt that I could have gone really low if I sank some of my putts," he added.
Panuphol, who is hunting for his first Asian Tour title, played blindly on the last three holes as sporadic rain in the afternoon fogged up his glasses. The highlight of his day was three straight birdies from 14 including a chip in from 15 yards on hole 15.
"The rain was pouring down and I didn't bring my umbrella, which wasn't smart at all. I was drenched going into the last few holes and the rain started to fog up my glasses! I was playing blindly in the last three holes. I kept my rhythm going so I'm happy with that," said the 19-year-old.
Makitalo, a graduate from Qualifying School, was two-over for the day after 10 holes before a 30-yard chip in eagle-three on 11 turned his fortunes around as he added three further birdies on his way home.
"I had nothing going my way in the first 10 holes. I was hitting it so bad until the eagle turned my game around. Hopefully we get some people around tomorrow because I tend to focus more and don't do stupid things when people watch me!" said the 31-year-old.
An in-form Bhullar kept his bid for a first Hero Indian Open title alive as he peppered the greens with acute iron play.
"I felt good and was enjoying myself because I found a lot of fairways and hit a lot of greens in regulation. I'm still looking forward to hitting some low numbers in the next two days," said Bhullar, currently in fifth position on the Order of Merit.
The halfway cut was set at three-over-par 145 with a total of 81 players making the weekend rounds.
Scores after round 2 of the Hero Indian Open 2012 being played at the par 71, 7068 Yards Karnataka Golf Association Golf Club course (a- denotes amateur):
132 - Richie RAMSAY (SCO) 66-66.
135 - Panuphol PITTAYARAT (THA) 67-68, Chapchai NIRAT (THA) 67-68, Jaakko MAKITALO (FIN) 67-68.
136 - Angelo QUE (PHI) 68-68.
137 - Thaworn WIRATCHANT (THA) 69-68, Gaganjeet BHULLAR (IND) 68-69, Kwanchai TANNIN (THA) 71-66, James MORRISON (ENG) 66-71.
138 - Adam GROOM (AUS) 70-68, Shiv KAPUR (IND) 67-71, Arnond VONGVANIJ (THA) 71-67, Simon GRIFFITHS (ENG)
70-68, Adilson DA SILVA (BRA) 70-68, Scott BARR (AUS) 70-68, Jason KNUTZON (USA) 68-70.
139 - Berry HENSON (USA) 70-69, Mardan MAMAT (SIN) 69-70, Kalle SAMOOJA (FIN) 67-72.
140 - Prom MEESAWAT (THA) 72-68, Zaw MOE (MYN) 67-73, Namchok TANTIPOKHAKUL (THA) 69-71, S. CHIKKARANGAPPA (am, IND) 72-68, Scott HEND (AUS) 71-69, Jyoti RANDHAWA (IND) 72-68, Chinnarat PHADUNGSIL (THA) 75-65, Chiragh KUMAR (IND) 69-71, Joonas GRANBERG (FIN) 72-68, Panuwat MUENLEK (THA) 70-70.