Introduction: Measuring Rate of Fire With Audacity

Ever wondered what the rate of fire (herafter ROF) of your airsoft/paintball gun is? This is a guide to the simple process of using the audio program Audacity to measure your rate of fire.

What you need:
Gun
Microphone for recording ( I use a simple USB mic)
Computer
and Audacity, which can be downloaded free here:
http://audacity.sourceforge.net/

Step 1: Record the Gun

Put the mic somewhere near the barrel record at least one second of continuous fire.
It should look like the picture below.
Each large peak represents the gun firing. small peaks in between are the guns parts moving. only count the large peaks.

Step 2: Analyze Data

Now simply use one of these methods
1:Count all the peaks and divide that number by the total length of your sample ( in seconds)
2: take a one second sample of the data and count the peaks in it

In both cases, the resulting number will be your ROF in shots per second ( or hertz, if you like )
to get rounds per minute, multiply by 60

the sample below yielded a time interval of 1.95 seconds and 39 shots, giving a ROF of 20 rounds per second, or 1200 rounds per minute