Border Issues - magazine capacity limits?

So I went to pick up a few items at the mailboxes today. I got a G-code holster, a low powered bolt for my mp9, and a 48rnd mp9 mag. Knowing our friendly Canadian border guards, I got a yellow slip to be searched for firearms and firearm related parts (which I don't blame them since I'm bring a bolt back). So once they get back from the 5 minute search (expecting for them to say something about the low powered bolt), they tell me that they have a problem with the 48rnd KWA MP9 mag. They said "You are not suppose to have it". I replied about how Airsoft retailers in Canada sell 48rnd mags to 5000rnd mags and how I understand if it was a real firearm why they would have an issue with it.

Is there a legal limit for airsoft mag capacities or are they not up to date?

[lupo]

1 of 2 possibilities , the inspecting officer is unsure of the rules so went with firearms related. Or they have changed the rules.

This is the first of anything I have ever heard from the CBSA in regards to Airsoft ammo capacity of mags whether they are GBB mags or AEG mags. Unless rules have changes again on Airsoft products with CBSA, I'm not sure what the reason would be for them to say this. Interesting.

They haven't changed the rules, this officer is going off real mp9 mag capacities which is ten rounds and he isn't sure of the rules so the easiest thing is to detain. I hope you get it back as you should cuz it is not illegal.

They haven't changed the rules, this officer is going off real mp9 mag capacities which is ten rounds and he isn't sure of the rules so the easiest thing is to detain. I hope you get it back as you should cuz it is not illegal.

Sorry, I should have included in my OP that they didn't take the mag away. 2 officers went to search my car (It seems like the first officer didn't have a clue what she was doing). The first officer came back and said that I'm not suppose to have it. What grinds my gears is if I'm not suppose to have it, why did they let me keep it (I'm not complaining, I just hate seeing my tax dollars hire people like that).