It's bad because the rate of fire is too high for the stock spring to keep the piston up with the gears. The result of high ROF setups too high for the gun is that the gears return to wind the piston before the piston gets back in to position and you end up grinding the teeth together before the racks are ready to cycle again.
Nobody ever said that higher mAh rated batteries are hard on the motor. It's only hard on your gears and piston teeth if your spring is low powered!
Here, let me post it again, in case you missed it the first time around:
Quote:
|
Originally Posted by ILLusion
Generally speaking, the main controller of rate of fire is voltage and current and the controller of how long you can shoot for is the capacity of the cell.
Larger cells (such as sub-C versus 2/3A [mini] cells) and even larger capacity similar cells (such as 4200mAh versus 2700mAh sub-C cells) have lower internal resistance within the cell. Basic physics tells us the relationship between V (voltage), I (current) and R (resistance). As resistance goes down, current is affected (since voltage stays the same) - and is why we notice a higher rate of fire with very large packs compared to smaller packs, even though voltage ratings are the same.
Even comparing a Sub-C 1700mAh pack to an A-cell 1700mAh pack, you will notice the sub-C pack has a higher ROF and seems to crank a spring with more gusto.
There are other factors that affect the rate of fire and how long the cell will last. For example, back to the 1700mAh Sub-C versus A-cell comparison again - a sub-C pack lasts longer than the A-cell. Why? Back to the internal resistance issue. The extra energy contained by the added resistance has to be released somehow. In the case of this chemical reaction, the extra energy is released as heat - wasted energy.
In a world of perfect atmospheric conditions, perfect cell production with 0% contamination and perfect cell mixtures and equality in a pack; yes... the rule of thumb of a 1000mAh charge lasting 1 hour at a draw of 1000mA or 1000 hours at a draw of 1mA. But that can only be used as a very general rule of thumb.
ALL of these reasons are why it's never recommended to jump to a high mAh pack when you have a low powered (stock) gun. I've seen pistons ripped to shreds in less than 10,000 rounds with 8.4v 2400mAh NiCad packs. Tokyo Marui's actual recommended pack for stock guns in sub-C form are 1300mAh!
Experienced tuners and shops do NOT recommend any higher than 1700mAh large packs for stock guns for this very reason! 4000+mAh packs lead to quick deaths for stock guns.
Higher capacity is NOT always better because in what I've just written above, higher capacity also means much more than just how long you can shoot for!
One way to balance it out if you MUST go to very high capacities on low powered guns is to drop the voltage level, which as the test in this thread proves, is still very effective for airsoft, even when running at 7.2V.
Depending on your size constraints, the stress to your motor and the size of your packs, your gun may be able to run at 6 volts? Who wants to give it a try?  |
If you don't understand the theoretical concept based on my explanations above, here is a perfect test:
Use a fully charged 8.4v 600mAh mini battery to fire a burst through a gun. Any gun. Stock or upgraded.
Now use a fully charged 8.4v large capacity battery pack... 2400mAh NiCad, 4600mAh NiMH, whatever. Doesn't matter. Either one will prove the theory. Fire a burst through the same gun with that pack.
Notice the difference in ROF? Despite the packs voltage rating being the same at 8.4volts, the larger pack has a markedly higher ROF, especially when the gun is fully upgraded. This is due to the lower internal resistance of the cells.
Ohm's law (V=IR) states that if voltage stays the same, and resistance goes down, then applied current goes up.
The result? Higher Rate of Fire with higher capacities due to the nature of differences in different capacity cells.