Benjamin NP2 surprising turn of accuracy after being shelved for a year

If you look at my member since you will see about the time I purchased the Benjamin. One of the reasons I joined the forum was because I just couldn't get any accuracy out of the thing. I had actually shelved the thing because of how it bounced all over the place
While deer hunting I realized there are a huge number of squirrel in my hunting grounds and so broke out the NP on a whim and dusted it off, not wanting to use my 357.
First shot I realized there was a huge difference in how the recoil felt much lighter. I tore it down cleaned and oiled it and shot again. Recoil didn't change, I don't have a crony so I set up a 1/2 inch osb target and started shooting at 20 yards was punching through so moved to 50 with still good results with 3 out of 5 shots punching through.
Went ahead and started getting scope zeroed in and realized that I was getting golf ball 5 shot groups.
While I don't have a crony I know my fps is a bit slower but still if I can punch holes in OSB at 20 to 50 yards it should be plenty of power to hunt squirrel with.
I don't know if perhaps the gas ram leaked down a bit or what but it has really tamed down.
Anyone experienced something like This?