DBoys M4 Motor and Battery Rate of Fire Tests
Saturday, September 29th, 2007As I mentioned in my last post, I decided to do some testing on the difference in rate of fire with a stock DBoys Full Metal M4A1 and different motors and battery voltages. At the time I had available to me the stock motor that came installed in the M4, a Tokyo Marui EG700 motor and a Systema Turbo motor. Batteries used for testing were the standard 8.4v mini battery which the M4 came with and an Intellect 1400Mah 9.6v battery.
Onto the tests..
To calculate the average rounds per second, I used my laptop with a standard pc microphone and used Audacity to record the sound of the gun firing. Each wave peak recorded and graphed by audacity can be counted as a single shot. For each test, I fired one 2 second burst followed by a 3 second burst.
From the sound wave produced in audacity, I then counted the number of peaks in a given second. I took 3 seperate seconds and calculated the average based on those. Below is a table of the results achieved. Note that there is no figure for the Systema Turbo motor running on the 8.4v battery, the cheap batteries that come free with clone AEGs do not appear to be powerful enough to push this motor with a 1 Joule (or close to it) spring installed. However I have tested with a good quality 8.4v battery and it ran quite well, although it was at a skirmish so I was unable to record the rate of fire at the time.
| ROF | 8.4V-1 | 8.4V-2 | 8.4V-3 | 8.4V Average | 9.6V-1 | 9.6V-2 | 9.6V-3 | 9.6V Average | |
| Stock | 11 | 11 | 12 | 11.33 | 13 | 14 | 14 | 13.67 | |
| TM EG700 | 11 | 11 | 11 | 11 | 14 | 14 | 14 | 14 | |
| Systema Turbo | N/A | N/A | N/A | N/A | 17 | 17 | 17 | 17 |
And while we’re at it… here’s a nice shiny graph of the whole lot:
Motor and Battery Rate of Fire Comparison
It should also be noted that the Systema Turbo motor is a very heavy drain on a battery, the Intellect 1400Mah battery I used lasts less than a thousand rounds, so you pay a price for that kind of rate of fire.
Interestingly the stock Dboys motor and the TM EG700 motor performed exactly the same, running with a 9.6v, the TM motor did average 14 rounds per second as opposed to the stock motor’s 13.67, however this is not a significant enough difference to be conclusive. Physically the two motors are identical and performance wise they also appear to be the same.
There’s not much more to say on the matter really, the results above say everything I could, any questions or comments though, feel free to click the comment button below.
Oh and while we’re here, here’s some nice pictures of the various wave forms recorded in Audacity:
8.4v Stock Motor
8.4v TM EG700 Motor
9.6v Stock Motor
9.6v TM EG700 Motor
9.6v Systema Motor







