The MMG (Medium Machine Gun) used by the Indian Army is the 7.62x51mm NATO FN MAG, which is locally manufactured and designated as the Indian Small Arms System (INSAS) MMG or simply IMG (Indian Machine Gun).  

Key Features of the MMG in Indian Service:
1.Caliber: 7.62×51mm NATO (standard heavy rifle round)
2.Type: Belt-fed, gas-operated, air-cooled machine gun
3.Effective Range: ~800–1,800 meters (depending on role)
4.Rate of Fire: ~650–1,000 rounds per minute (adjustable)
5.Weight: ~11–12 kg (gun only), ~15–16 kg with tripod
6.Feed System: Disintegrating metallic belt (50/100/200 rounds)
7.Muzzle Velocity: ~840 m/s  

Role in the Indian Army:
- Used as a sustained fire support weapon for infantry battalions.
- Mounted on tripods for defensive roles or bipods for assault roles.
- Effective against personnel, light vehicles, and suppressive fire in combat.
- Often deployed in border posts, counter-insurgency (CI) operations, and conventional warfare.  

Manufacturing & Variants:
- Ordnance Factory Board (OFB) initially manufactured the FN MAG variant under license.
- The Indian Army also uses imported FN MAGs from Belgium.
- Modernization efforts include potential replacements with lighter, more advanced MMGs.  

Comparison with Other Indian Army Machine Guns:
- LMG (Light Machine Gun): 5.56mm INSAS LMG or newer 7.62mm Negev NG7 (for mobile firepower).
- HMG (Heavy Machine Gun): 12.7mm NSV or Browning M2 (for anti-material roles).