Meant to point out on my previous post, too, but the size and, hence, tightness in the breech and also the thickness and hardness of the skirt makes one hell of a lot of difference too, Rhys. In many cases, more so than the weight.
Now, Phil mentions that after a couple of shots with the Heavies, we got used to the shot cycle and it did actually seem quite nice. And I think I believe that that is it and it's just a case of the user getting used to the new shot cycle feel.
But then I have sometimes wondered....."what if" .......and maybe this is a little "far out", but what if the gun ACTUALLY LEARNS THE PELLET to a degree. Well, when I say "gun", more specifically the SPRING? After a few shots can the spring metallurgy actually learn the characteristics for the most efficient shot cycle, re-arranging its composition slightly to cater for the very slightly different acceleration, distance travelled on the forward stroke and the subsequent bounce?
Discuss........politely!