Not trying to be a troll or an ass Dave, nor am I trying to make a mountain out of a molehill, but can you post a link to factual information regarding this "law" you speak of?
If what you are saying is true in that there is in fact a "law" requiring our mags to have welded floor plates..... Every person that posesses such unwelded mags, lawfully obtained or not .... Is right at this moment a crimminal and in posession of prohibited devices.
This is kinda a big deal is it not?
I'm surprised the importer did not appeal and cite the fact that thousands of these mags exist legally in canada as we speak.
The law has not changed.
As I understand it there are two things at work here.
One is the ability to import stuff ... somehow the standards have changed over the last year or so. I was in the process of buying mags for resale and was told that none were available at the time as a large shipment had been seized due to the fact that the mags were of the type whose capacity was limited by use of a large follower.
The other is a legal precedent which stated that magazines were required to be limited in such a way as to not be "easy to convert". I do not have access to this ruling and would have to search for it. It dates back to the early days of the Campbell laws and have probably been mimicked in the "guidelines" concerning prohibited devices.
Yet another legal precedent occurred within the last year or two and involved disassembled mags. Remember when we all thought "mag kits" were ok? Well, this judge found that they were not, and in fact that the mag body was the critical component in determining the legality of a magazine.
I mention this case as it may have been the catalyst which emboldened Customs to further restrict what could be brought into the country, mag wise. This would explain why the long follower mag was allowed in for quite some time, then suddenly, was disallowed ... we are back to rivets, which one might argue, alter the mag body.
So how do the welded bottoms qualify? I suppose since they are welded to the body one could argue that the body has been somehow altered. I admit that pinning the baseplate may not be the best alternative, but it is something. The safest recourse at this point is to drill the body of the mag at the appropriate place and rivet it. This is the standard acceptable even for imported magazines these days.
I will see if I can find the legal references for you, but I do not have them to hand. I do know that in the course of my regular contact with importers, that these are the issues ...
Now, are you risking immediate arrest for having incorrectly pinned mags? That is a different question entirely. I was told by a VPD officer that in the early days of Campbell's Act (may she burn in hell) any attempt to limit mags meant that there would be no further action taken. This would include the simple insertion of a wooden block to limit capacity, for example. As time has progressed, I suspect that this attitude has changed but not in a uniform way. So we are left with uncertainty and a policy which is gradually becoming more restrictive.
In my view it is important not to fall afoul of any possible law or interpretation thereof which might threaten one's ability to own and enjoy firearms.
People should not be deceived by the fact that some have been leniently treated in certain circumstances. Catching a break on a traffic ticket does not invalidate the laws on speeding .... you can still pay the price if you break the law, and in this case the consequence is far more serious.