IMHO, the arguement that AR10 and SR25 are variants of AR are very weak.
First of all, the linkage is so remote - the sharing of characteristics/design principles of gas systme is not an arguement. Otherwise everything will be a variant of another.
The only thing AR10 shares with AR15 is the firecontrol parts - but this is pretty weak too. A variant implies that it is a "variation" of the original. A variation means the original platform itself is maintained and that some other characteristic is added or subtracted afterward. It is like changing the suspension of the car but the chasis must be the same. In this case, the AR10 does not even have the same chasis as the AR15. They may use the same gas tank and the windshield wiper fluid containter.......this is the biggest blunder of the RCMP lab. THey paid for it later on though. Now if they think those 2 parts in the lower make something an AR15 variant, than what is an AR180b?
Precedence A: an AR trigger group combined with a DI gas system is an AR variant - no matter if it is wrong.
Precedence B:So apparently they got caught - so ok, if a rifle use an AR15 trigger group, that makes an AR180 variant not a AR180 variant. So why isn't the AR180B restricted because apparently the AR15 trigger parts is the decsion point? So the combination of AR trigger parts with whatever upper system other than the direct gas system of the original AR15 nullifies the AR linkage, but it also nullifes the linkage of the receiver/gas system/boltgroup
They set a precedence with AR10, and then they set a second precedence with the AR180B.
Last lets examin the LWRC - It has a gas system that is different from the DI system of the original AR and uses AR15 trigger parts. Now apply Precedence B. They don't comply, take it to the lawyer - a 100% win.
The lab is just a lab. When it comes down to important matter based on interpretation, things are argueable. It is a just a matter of determination as well as cost/benefit to use legal counsel.
In fact, the whole AR15 business is based on mistaken interpretation of the OIC.- which specifically prohib M16 and its variant, while the AR15 is not a variant of M16. M16 is a variant of AR15. Any half serious legal challegne will completely overturn all the decision ever made on the AR15. THe only thingthat stops people from admitting mistake is embarrassment ot the organization and political cost.
I urge everyone who is a member of the NFA and CSSA start using their membership privilege and FEE to fix these problems instead of moaning their illogic - illogic in intrepertation of reg. means lawyer time and winning- which means these are the jobs of paid gun right groups.