Here's a link on how to do it.
http://www.rimfirecentral.com/forums/showthread.php?t=94809&highlight=objectiveI've adjusted the parallax on four or five of my scopes. It's no big deal.
One tip I'll give you is if the front ring cannot be loosened by hand try some duct tape. A full width size piece wrapped once or twice around the ring, then flip it over a 1/2 turn, wrap some more, wrinkle it, wad it up and then another couple of wraps. The object of all this is to have a big wrinkly wad of duct that you can grab on to. It works and you won't have to buy a strap wrench.
