I think the technicians point is that all 10-22 magazines are inherently designed for all 10-22, including the charger. On a technical point of view, he isn't wrong. However, the RCMP bulletin (
http://www.rcmp-grc.gc.ca/cfp-pcaf/bulletins/bus-ent/20110323-72-eng.htm) doesn't end after alinea 1. There's points. But let's talk about the first one first:
1. Magazines designed or manufactured for both rimfire calibre rifles and handguns
Magazines designed to contain rimfire cartridges and designed or manufactured for use in a rifle do not have a regulated capacity. However, magazines designed to contain rimfire cartridges and designed or manufactured for use in a semiautomatic handgun are limited to 10 cartridges. Magazines designed or manufactured for use in both rifles and semiautomatic handguns are subject to the handgun limit of 10 cartridges.
Example:
Smith & Wesson M&P 15-22 rifle and 15-22P pistol chambered for 22LR caliber:
•the 10 round magazine is unregulated
•the 25 round magazine is a prohibited device
Example 2*: The Ruger BX-25 magazine, chambered for 22 LR calibre, is designed and manufactured for use in the Ruger SR22 rifle, the 10/22 family of rifles/carbines and the 22 Charger handgun. As a result, this magazine is a prohibited device unless modified so its capacity is 10 cartridges or less. (*This information was not included in the original version of this bulletin, but was added on 2013-09-05.)
I'm not 100% familiar with the history of the BX-25, but given that Ruged markets the thing for the 10-22, SR-22, 10-22 takedown and the charger, it seems that it is indeed "designed or manufactured for use in both rifles and semiautomatic handguns", and therefore prohibited. Had Ruger sang a different song when the charger came out (saying the magazine is expressely designed for the 10-22 carbine, we only support the use of rotary 10 rounds mags in the charger), the story might be different today. The hot lips and steel lips and the drums (and most other aftermarket mags), however, have entirely different stories: they were on the market before the charger even existed. Therefore, one could not possibly argue that they were designed for the charger. One could however argue that they are nowaday manufactured for the charger, which is true on a technical point of view only. The argument is very week though, and it completely crumbles if you take into account the market presence of the charger (nobody would manufacture mags for a pistol that's all but impossible to find) and it would still only apply to magazines manufactured before the charger was brought to market.
Now let's see alinea 4:
4. Magazines designed for one firearm but used in a different firearm
The maximum permitted capacity of a magazine is determined by the kind of firearm it is designed or manufactured for use in and not the kind of firearm it might actually be used in. As a consequence, the maximum permitted capacity remains the same regardless of which firearm it might be used in.
Example:
The Marlin model 45 (Camp Carbine) rifle chambered for 45 Auto caliber uses magazines designed and manufactured for the Colt 1911 handgun, therefore the seven round and eight round capacities are permitted.
Given that the aftermarkets magazines were designed and (mostly) manufactured before the charger even existed, I believe this is the point that stands. Until a court decides where the tails and where's the head, we can't know for sure, but I'd say that it's legal to use a butler creek in a charger, not that it's illegal to own a BC.
It all boils down to wheter or not the magazines is designed or manufactured for use in a pistol or a rifle, for which the technical possibility to use it in that rifle or pistol is merely ONE component. In the end, intentions of the manufactrer would actually be a factor.
It belongs to our elected officials to write the laws (which currently are a complete cluster####) and to the courts to interpret it. The RCMP lab technician's job is merely to give a technical opinion/fact, he has given it (the mags can be used in the charger), and that's pretty much it. From what I get, the lab technician's word don't have any more meaning than if he'd said "the 1911 magazines can be used in the marlin model 45". Which is technically true, but doesn't make those mags prohibited.