What about the $500 ITAR Exemption?
As of July 2013 - the United States allows for the export without an export license of certain firearm-related parts and components (22 CFR 123.17(A))
Does not apply to any parts/components related to Shotguns (these are regulated by the U.S. Department of Commerce rather than the U.S. Department of State, and there is not equivalent exemption for shotgun parts in the Export Administration Regulations).
Does not apply to ammunition-related parts and components. These are classified as “Category 3 on the U.S. Munitions List, while the exemption only refers to “Category I(a) firearms.”
Does not apply to “Significant Military Equipment,” which includes any firearm itself.
Does not apply to any parts at all related to fully automatic firearms, even if you're planning to use the part on a semi-auto variant.
Also does not apply to barrels, cylinders, frames (receivers), or complete breach mechanisms.
Exemption can only be used and claimed by a DDTC Registered Exporter (not just any business, nor a foreign individual traveling in the US).
The Registered Exporter, still must file documentation online (using the Automated Export System, or AES) to notify the government that the exemption is being used, including the item description, tariff code, value, weight, date of export and Port of Exit.
By law, orders cannot be broken up into smaller shipments to meet the $500 threshold
This is why Brownells can export small parts to Canada without an export permit, but YOU CANNOT GO TO CABELAS AND BUY $500 OF GUN STUFF AND BRING IT HOME WITH YOU.