Just so we are clear you are dispatching a birds every 3-4 minutes. Not butchering. If so dang your fast!!I use the carotid artery cut. Right below the jaw bone and hanging upside down in a cone over a feed trough full of pine shavings. Me and 2 other people do 60-70 in a day a couple times a year that way. I think I'm reluctant to try any other method because we have a good system down. We can butcher that amount of birds at a rate of 3.5 minutes per bird so I know it can work quickly if you do it correctly - takes a bit of practice though. If only butchering a couple at a time, it could be worth it to try a few different methods to see which works best for you and then you know for next time.
