Adding Capacitors

The Gun
Using a Tokyo Marui Mp5A4 with a small tamia connector, and a 9.6V 1600 mah battery. The gun is tuned with a 120 spring and 32:1 gears, so (because of the gears) the rate of fire is quite slow. The motor pulling it is a EG700 motor and it's because of this old motor the gun uses torque gears to pull a relative low load. But it's not the gun but the effects of capacitors that this guide is about. So it really don't matter what gun was used.

Base line
The first setup we look at are the standard gun with just the 9.4 volts 1600 mah battery attached. With this setup the gun shoots just around 12.1 rounds per second. So that's the baseline of this test.

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To improve from the standard the capacitor is added to the setup. I have wired in a capacitor that is attached with dean-T plugs that should be able to pull 60 amps. All capacitors have a voltage rating, this is the maximum voltage that the capacitor can handle without blowing up. So make sure you leave plenty of room e.g. 20V capacitors. They also have a capacitance rating, that are how much they can store. I used a 10K capacitor, because it’s the biggest I have but if you have smaller ones you can add more to add up the capacitance. When adding more they should be added in parallel.

With capacitors
With this capacitor in line with the battery the rate of fire increased a bit to around 12.4 rounds per second. Using the same battery with near the same voltage output. So there was a small increase, but it's not a mind blowing change.

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When comparing the 2 shootings with each other it becomes clear that the change did not come without a penalty. Because of the added connectors the total circuit resistance increased a tiny bit, so the time from trigger pull to first shot is released increased a bit also. So in single mode the gun is slower. But over all the gun is improved, meaning that over a 300ms (0.3 sec) the capacitors has cached up with the none capacitance version, and from that point on put's out faster. But keep in mind that if you wire the capacitors without extra plugs it should have the same trigger response with the improved rate of fire.

But just to compare with I also added a 7.4v 2200mah 35C lipo (the top one) with no capacitors, and that gives out a much faster trigger response and also 14.2 rounds per second, so if you have the money its better to get a good lipo battery than to add capacitors.

So in conclusion: Capacitors can improve rate of fire! But compared to a better battery the capacitors stand no chance.