Prakash, 25, took a big lead in the qualifying stage itself by logging 563 and then continued his good form in the final round to tally 661.4 that placed him far ahead of second-placed Vijay.
Vijay, who has earned a quota place for the 2012 Olympics in the 25M rapid fire event, tallied 647 for silver.
Shruti Bhattepatil of Maharashtra upstaged veteran Anjali Bhagwat to clinch the gold in the women’s air rifle event.
Results: Men: 50M free pistol (final): Om Prakash (Army) 661.4 (563+98.4) 1; Vijay Singh (Army) 647 (558+89) 2; Amanpreet Singh (ONGC) 646.9 (549+97.9) 3; PN Prakash (Karnataka, 644.9) 4. Women: Air rifle (final): Shruti Bhattepatil (Mah) 499.4 (395+104.4) 1; Nampi Das (WB) 499.2 (396+103.2) 2; Anjali Bhagwat (Mah) 498.4 (395+103.4) 3.
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