Part of the problem is that while someone hunting will fire a shot here or there, that once you try to firing more than a handful of shots from one location, it draws the attention of people from a far distance.
If you're going to shoot on any public land in Southern Ontario (say from Orillia south for arguement's sake), you'll need to confirm that shooting is allowed in the area in question by contacting the appropriate authority, research any other pertinent bylaws, and if you've never shot there before do a thorough reconnaissance of the area in question so that you not only find a spot with a good backstop, but confirm the distances from and general direction of any houses, travelled roads ect. It would be best yet if you get as much information as you can in writing and take it with you whenever you head out, and go with someone else so that it's not your word versus someone else if they call the police and claim that you've done something wrong.
That said, the Copeland forest is a large tract of land, and if you could find out precisely the area in question where shooting is allowed, you'd probably do well to go there. Second to that, there is also Brighton WMU just off the 401 about two hours East of Toronto, where people shoot centrefire, shotguns and .22. While the Simcoe County Forests are generally open to hunting, I'd check with them first to see if they have any rules against target shooting.
"If you're in the wilderness , in ON, with a firearm you're hunting. The onus is on you to prove otherwise."
This latter rule applies to areas from about Muskoka northwards where a small game hunting license is not valid between 15 June to 01 September. It should not be an issue south of that region, but could come into play if someone chooses to shoot around their cottage in the summertime.
Though I don't want to discourage people from using clubs, we need to better establish the practice of target shooting on public land in Southern Ontario so that people will get used to it as a fact of rural life. There's lots of suitable places for it, though without doubt also lots of people out there who equate plinking with a .22 to paramilitary terrorist training. If enough people could gather together information about plots of public land available for hunting and target shooting in Southern Ontario, including information on municipal bylaws or at least where to find out about them, that would probably be of considerable benefit to lots of people here. I'd be willing to help out wherever I can.
Regards,
Frank
Here is the link 
