Canadian Sources of Newer Cartridges

Not a new topic. I have raised similar questions myself in the past.

I am trying to locate a Canadian source for single sales of cartridges introduced in the past 20 years. I have a lengthy want list! And I doubt that I am alone. I am hoping someone can identify either a vendor, or someone who sells singles as a sideline to their firearms business.

North of the 49th parallel there is far less trouble in finding black powder and older smokeless powder cartridges. I can and do buy those without any problem.

I’d be interested in hearing from a source, or from a fellow member who can direct me to one.