This is extracted from the Canadian Firearms website. It deals specifically with Firearms, not Ammunition, but there is a phone number which may be helpful:
Q. Do I need an export permit to take or ship a firearm out of Canada?
If the firearm is being exported to the United States, you only need an export permit if the firearm is prohibited. When the export and import provisions in the Firearms Act and its supporting regulations come into effect, an export permit will also be required for restricted and non-restricted firearms.
An export permit is required for any class of firearm being exported to a country other than the United States, even if the export is only temporary -- for example, if you take a firearm to another country to hunt or to target shoot. When you apply for an export permit, you must include an import permit from the country of destination and from any other countries that the firearm will be travelling through en route.
To get an application and more information, please contact the Export Controls Division of the International Trade Canada at 1 800 267-8376 or (613) 996-2397, or by sending a fax to (613) 996-9933. If you send a fax, please include a mailing address where they can send an application form.
