Quote Originally Posted by Shed tuner View Post
counteracted by the stroke reduction....
Yes, mine has the reduced stroke but when using the 8.4 JSB's in any head size it creates a bit of buzz from the spring which I am sumising is caused by some greater surge from the piston. It even did this with the higher pre-load from the original spring length. The m.e. with all 3 weights of jsb is identical though so if your theory on surge and m.e. across different pellet weights is correct it shouldn't be any different.