What is your groupings like?
My Stoeger is extremely hold sensitive!
about 1cm groupings on 20m is about the best it can do.
And to achieve that i really have to focus on how i hold the thing.
Also it is very picky on ammunition!
I have a feeling mine shoots hot, mine actually shot better when it had dried out
and was eating away on the seal then it did after I lubed it by the book.
Be very aware of how you hold it.
Try some different pellets.
Wash and lube half of the pellets you try to see if it makes any difference.
Give the barrel a proper clean.