Isn't it only a 9v that powers most stun guns?
Yes and 4 AA at 1.5 volts a piece. The voltage is not impressive until you run in through a transformer inside the stun gun itself.
Stun guns are ALL voltage, no amperage. A simple 9volt, run through a small step up oscillating transformer can boost a voltage push up to 15,000 volts or higher with tasers, for a brief shot.
http://en.wikipedia.org/wiki/Electroshock_weaponPrinciples of operation
Electroshock weapon technology uses a temporary high-voltage low-current electrical discharge to override the body's muscle-triggering mechanisms. The recipient is immobilized via two metal probes connected via metal wires to the electroshock device. The recipient feels pain, and can be momentarily paralyzed while an electric current is being applied. It is reported that applying electroshock devices to more sensitive parts of the body is even more painful.[1] The maximum effective areas for stun gun usage are upper shoulder, below the rib cage, and the upper hip.
High voltages are used, but because most devices use a high frequency alternating current, the skin effect prevents a lethal amount of current from traveling into the body. The resulting 'shock' is caused by muscles twitching uncontrollably, appearing as muscle spasms.
The internal circuits of most electroshock weapons are fairly simple, based on either an oscillator, resonant circuit, and step-up transformer or a diode-capacitor voltage multiplier to achieve the continuous, direct, or alternating high-voltage discharge. It may be powered by one or more batteries depending on manufacturer and model. The output voltages without external "load" (which would be the target's body) are claimed to be in the range of 50 kV up to 1000 kV, with the most common being in the 200 to 300 kV range. However, since air has a dielectric breakdown (Emax) of 3000 kV/m, it is clear that the spacing of the electrodes will not permit the upper range of claimed voltages (900 kV representing a minimum electrode spacing of about 30 cm). The output current upon contact with the target will depend on various factors such as target's resistance, skin type, moisture, bodily salinity, clothing, the electroshock weapon's internal circuitry, discharge waveform, and battery conditions.[2][3]
It will light your ass up regardless, the "little" 9volt can generate quite a nasty little tingle to the body when stepped up.
Current or (amps), is what kills you. The electric chair was standard 240VAC, but a transformer through a frankenstien resistor, created well over 250 to 500 amps. THAT is what fried the condemned.
Can also be done with a car battery.. If you can utilize the amps...