battery problem, smaller battery won't cycle

[Fox Hound]

I finaly shimmed my gears to perfection and im just so stoked how well my gun fires. I elminated the annoying humming sound when firing now it only sounds like a pop pop pop.

Ok so heres the thing, i also rewired the gear box because i really wanted to keep the CQBR look so i had the wires routed to the side and into a ready mag. I have a 9.6v 2000mah battery that i have in the magazine but it wont cycle the piston, all i hear is a faint clunk.

But when i use my crane stock which is at 9.6v 3300mah it worked perfect, and there is no way i can fit this into the ready mag.

BTW im running a m120 with a systema magnum if that helps. I can't figure out why this isnt working. The motor draws about 10amps i think and both batteries should be efficient i think.

any ideas?

[Steggs]

Dude, I had the same problem with my m120 wouldn't fully cylce with a mini. I have been told to try torque up gears but I think using a large type battery is the real answer.

[Jimski]

Steggs is right.You're not getting enough power out of the small battery to crank the M120.
you need more mAh, or a lighter spring (or cut some coils)
(the legend says torque up gears and a mosfet could help you, but I dunno for sure...)

is it Nicad or Nimh btw?

[Fox Hound]

i dont think a transistor will help, but if all else fails i think i may have to use my crane stock.

damnit i've opened and closed my gear box like 20 times doing trial and error, listening. Sigh here we go again.

[Fox Hound]

anyone know the largest battery i can fit into a ready mag, this is a real hasstle to rewire it again

[hutch1970]

1300 mah diffrence- volts the same. Indepenent wiring from the rear crane set-up? Have you checked to make sure your wire being routed to the ready mag is not grounding somewhere? Is that batt. taking a full charge? Are the wire connections in that area getting juice through? On a side note, have you ever considered Li-polymer batts? Smaller, more powerful. I use 11.1 15c 1250 mah with awesome results( I use m120 springs) .

[The Saint]

Originally Posted by Steggs

Dude, I had the same problem with my m120 wouldn't fully cylce with a mini.

It's not a mini, though. Minis only go up to about 1500mah. I'd pay attention to Hutch's suggestions, it's really weird that a 9.6v @ 2000mah can't even cycle M120.

[Kos-Mos]

not grounded or els it would not do a "chuck" sound.

Might be wired reversed though. So the sound you would get comes from the anti reversal latch engaging.

Check that.... might be it.

Mosfet can help because you get about 100 times less resistance in your overall system.

[Fox Hound]

Originally Posted by hutch1970

1300 mah diffrence- volts the same. Indepenent wiring from the rear crane set-up? Have you checked to make sure your wire being routed to the ready mag is not grounding somewhere? Is that batt. taking a full charge? Are the wire connections in that area getting juice through? On a side note, have you ever considered Li-polymer batts? Smaller, more powerful. I use 11.1 15c 1250 mah with awesome results( I use m120 springs) .

The trigger assembly was intermitting with the gear box, i took this and fixed it. I did a continuety check. It all checked fine. i re wired it as well to replace all the damaged wire.

Saying this i THINK the battery is worn from the trigger assembly shorting out the battery constintly. When i bought this i was told that the battery did not last long, so i was wondering why because a 2000mah battery should last almost a day for some half a day.

I dont have another mini battery, just my crane stock battery to test and my power source only puts out a max of 5amps. So let the waiting begin i've ordered another mini

[Steggs]

Ok, when your down with yours get down here and help me with mine!!! Well the shimming part anyways!

[Drake]

Keep in mind cell size does matter, despite what the numbers might lead you to think. A small (2/3AA) 8.4v 1500mAh pack != large (Sub-C) 8.4v 1500mAh

[mcguyver]

Originally Posted by Drake

Keep in mind cell size does matter, despite what the numbers might lead you to think. A small (2/3AA) 8.4v 1500mAh pack != large (Sub-C) 8.4v 1500mAh

Yep, Drake is right. In the ready-mag or PEQ battery systems, the batteries are typically AA in cell size. Despite the MAH rating, the cross-sectional area of the cells does not generally allow for a high-current discharge at the same capacity as a sub-C cell size. If you tried a battery made with sub-C cells at 1700 mah for example, it would likely run the gun fine.

[Fox Hound]

Originally Posted by mcguyver

Yep, Drake is right. In the ready-mag or PEQ battery systems, the batteries are typically AA in cell size. Despite the MAH rating, the cross-sectional area of the cells does not generally allow for a high-current discharge at the same capacity as a sub-C cell size. If you tried a battery made with sub-C cells at 1700 mah for example, it would likely run the gun fine.

i believe the size doesnt matter as long as the specs are correct. If its 9.6V it has a potential of that, and the milli amp rating would only show how long it would last.

the Discharge rate of a 2/3A battery is 14amps, that is more than enough to work the motor. the motor will draw as much as it can and im pretty much confident that its the battery being weak since i can only draw about 8 amps now from 10amps.

[Kos-Mos]

battery type makes all the difference.

I can crank up my gun on a 7.2v 2000mAh Sub-C
Need at least 8.4v on minis.
And 9.6v in AA battery won't turn it (good quality batteries btw)

[mcguyver]

Originally Posted by Fox Hound

i believe the size doesnt matter as long as the specs are correct. If its 9.6V it has a potential of that, and the milli amp rating would only show how long it would last.

the Discharge rate of a 2/3A battery is 14amps, that is more than enough to work the motor. the motor will draw as much as it can and im pretty much confident that its the battery being weak since i can only draw about 8 amps now from 10amps.

Nope. You are wrong. I've been down this road before and figured this out years ago, just through trial and error. A 9.6v 2600 mah battery in the PEQ of an old M4 I had would not run an M110 spring, but as soon as I tried an 8.4v 2400 mah battery, it would run the gun all day. The 9.6v used AA cells, and the 8.4v used sub-C cells.

The discharge rate does not cover in-rush, which for an 8 amp draw can equal many times that, maybe 30 amps or more easily. 14 amps does not equal 30, and that's why your motor can't fully start and cycle the gun.