Sand pits, rock quarry, etc...

[ScubaD]

I see posts on here now and then about going to sand pits, rock quarries and other places or such. I know that you can legally shoot on a farm with the land owners written permission. But whats with the other places? how do get permission for sand pits and quarries, they aren't crown land so...???
I'm in Guelph, Ontario and other then the asking farmers or joining clubs, legally or gray area legally where else can you go? I had a friend tell me once that he took his new 12ga to the water front over lake Ontario in the back 40s, walked a bunch of trails to get a spot, and then just tossed some clays over the water, not sure if that was legal?

 

[sunray]

Most sand pits, rock quarries and other such places are usually owned by a construction company or the like and are posted as no trespassing. So is most of the land around Guelph. Lot of TO people own the area farms now and dislike hunting and hunters. The 'bunch of trails' would have to be on Crown Land(most of which is infested with hikers, pic-nickers, skiers and other riff-raff. Like the CL at Guelph Line and the 401 is.) or you'd be trespassing.
In any case, to be on anybody's land you need written permission. Really is best to join a club.