The key to a successful magazine (in my opinion) is maintaining a constant and high amount of advertising running in your book. Most specialty magazines are born from specialty retailers that band together to create a medium to help sell their product. And in some cases, the magazines are owned by the retailers.
I hope that if you embark on the project, considering the state of Canadian publishing, you will be successful. I think a Canadian Airsoft magazine would be cool, albeit, maybe unnecessary. I am sure you must have run some favorable to still be considering this project. So I wish you good luck!
MODT - Magnus Operator Development Team - tu fui ego eris