Resizing a mainspring

by B.B. Pelletier

I recently started writing more reports about the fundamental things that many airgunners would like to know. These are things you don’t have to know to shoot an air gun; but if you do know them, they can often help you recognize why your gun does what it does. You also don’t have to know what makes an automobile work; but when it stops working, sometimes knowing how it’s supposed to work can help you find the problem and fix it.

Today, I’m going to show you how a brand new mainspring is set to its operational length before installing it into a spring-piston airgun. It’s not necessary to do this; because, over time, the mainspring will automatically reduce in length after being in the spring gun under some tension and being compressed many times. If you do this first, it makes the job of spring installation easier in some cases. read more