Bedding is cheap and relatively easy. I'd also look at your manual re: barrel set up/swap. Take the barrel off, check all the surfaces that meet on the barrel and action. Reattach the barrel and ensure everything is torqued up to spec..
Bedding compound and plastercine $30
Trigger job $60
I'd be very surprised if these two things didn't make a marked difference but like i said, your groups weren't too bad for a someone who hasn't shot very much.