give you more hint...
Approx. Battery-to-Rounds Capacity: [NiCd] (on M120 Stock Gears, EG1000)
9.6v 600mAh = <500 rounds (Small) Sanyo KR600AE 9.5mOhm Internal Resistance
9.6v 1100mAh = 1,000 rounds (Slim) Sanyo KR1100AAU 19mOhm Internal Resistance
9.6v 1500mAh = 1,400 rounds (Fat AA) Sanyo KR1500AUL 16mOhm Internal Resistance
9.6v 1700mAh = 1,800 rounds (Fat-long AA) Sanyo KR1700AU 17mOhm Int. Resistance
9.6v 1900mAh = 2,400 rounds (Sub-C) Sanyo N-1900SCR 4mOhm Internal Resistance
9.6v 2000mAh = 2,600 rounds (Sub-C) Sanyo KR-CH 6.5mOhm Internal Resistance
9.6v 2400mAh = 3,100 rounds (Sub-C) Sanyo CP-2400SCR 4.5mOhm Internal Resistance
9.6v 3000mAh = 3,800 rounds (Sub-C) Sanyo HR-SCU [Ni-MH] 5.3mOhm Internal Resistance
Guns... lots of Guns...