Boy, if you want to get airgunners “lit up” on a topic, try discussing springer hold sensitivity. Some professional spring gun tuners will tell you there’s no such thing as hold sensitivity in a spring-piston air rifle, that there are only shooters who don’t know how to shoot springers properly. On the flip side, there are experienced spring gun shooters who will tell you that the aforementioned professional tuners are in desperate need of a physic.
Whether or not it is me or the gun, I can tell you there are times when I can’t shoot a spring-piston air rifle worth a darn and other times when I am pretty good. In other words, sometimes I’m a hero, and sometimes a zero. (By contrast, I shoot well with pre-charged pneumatic or pump-up pneumatic airguns almost all the time.)
Lately, I’ve been working on a theory of how to reduce the apparent hold sensitivity of springers. But before we get into that, a little background.
The thing that can make a spring-piston air rifle difficult to shoot well is the basic powerplant within it. When you cock a springer by pulling the barrel or a side lever or under lever back until it latches, you are compressing a spring. The spring remains under tension, like a sprinter in the blocks, until you pull the trigger. Released from confinement, the spring lunges down the compression tube, pushing the piston in front of it. This causes recoil toward the rear of the gun. As the piston reaches the end of the compression tube, it bounces off a wad of compressed air in front of it (at the same time air squirts through the transfer port, launching the pellet down the barrel), causing recoil in the opposite direction.
Now, here’s the really cool part: all this thrashing around of spring and piston within the rifle, the forward-and-reverse whiplash recoil, all of it happens before the pellet leaves the muzzle. (In a precharged pneumatic, by contrast, when you pull the trigger, a valve opens, air squirts down the barrel, driving the pellet toward the target, and there is a teensy amount of recoil to the rear. It’s all very dull, boring, and generally accurate as the dickens.)
It’s been my observation that if you inadvertently hold a springer with more pressure on one side of the forestock than the other (as many of us do), the gun will tend to jump away from the side with more pressure when the shot is triggered. I saw this graphically demonstrated with a Beeman R1 in .177. I had a 3-12 scope mounted on it, and it would shoot little tiny groups at 20 yards. The following day it would shoot little tiny groups, but half an inch away from the location of the previous day’s groups.
It drove me nuts. So one day, I took off the scope, mounted a peep sight and consistently shot little tiny groups in the same location all the time. I spoke with Steve Woodward about it, and we came up with a theory. First, when a springer jumps away from unequal pressure on the forestock, it tends to rotate around the center of gravity on the rifle’s long axis. Ideally, you would like the gun to rotate around the bore. But when you mount a scope on the rifle, you raise the center of gravity, which tends to exaggerate the movement of the bore and throw your shots off. The bigger, higher, and heavier the scope, the more you tend to throw your shots off (that is if you are not shooting with a perfectly consistent “hold”). The peep sight worked because it was light and low.
So, what to do? Well, here’s my working theory: to reduce apparent hold sensitivity in a springer, mount the lightest scope you can, and mount it as low as you can. This should raise the center of gravity as little as possible, resulting in more consistent shooting. I have tried this with one of my springers and it seems to work
But this is not written in stone; it’s just an idea I have had that seems to make sense. So, if you like, try it with your springers and let me know your thoughts.
Until next time, aim true and shoot straight.
– Jock Elliott