Drone handling is about holding the drone in the right position and giving the right stimulation.
Take the drone, upside down, in your left hand so that your thumb is under his throat and forefinger on thorax. Pressing fast and with determination in this position is sometimes all what is needed, to get the partial eversion happen, but to get almost 100% outcome tap the drone abdomen sides with one fast tap, with your right hand thumb and forefinger right AFTER you have pressed with your left hand (throat/thorax grip). It is crucial to make these pressings with determination and fast after each other.
When partial eversion has happened move the drone in another position in your left hand. Take the drones abdomen, which is now hard as rock, between your left hand thumb and forefinger.
The ejaculation is completed by pressing in the middle of the abdomen. Pressing the lower part of the abdomen (not in the middle) makes the ejaculation happen faster and with greater speed, but the down side of this that when pressing lower the semen sometimes jumps to your fingers, in which case the drone has to be discarded to avoid bacteria infection. The right position must be learned in practice. When pressing right in the middle or even little upward of the center it takes more time and pressure, but the ejaculation can be made to happen so that only all semen is nicely in one spot easily obtainable. Squeezing is done somewhat as a roll towards the end of the abdomen.
Polish insemination experts use 8 drones, I have usually taken semen from 10-15 drones.
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