Well thanks to the Canadian department of defence and some help with research, we can now comprehensively answer that question… and you will be surprised. It seems that the Police executive may have been better off to keep quiet while they had us all believing the previous interpretation of what we were allowed.
Beginning in the early 1700s, ordnance officials, from their headquarters at the Tower of London, divided the manufacture of firearms into locks, stocks, barrels, ramrods, and furniture—all of which they sought to purchase directly from subcontractors. Since different components for the same weapon were made in different locations, Tower officials oversaw the establishment of "Sealed Patterns" (sample firearms) to serve as exact models for gun makers. An Ordnance Office decree of 1722 led to a "standard army musket." And so the standard military pattern was born.
Anything can be a military pattern item, firearms, cups, trucks, and condoms, whatever. When a military force wants to purchase firearms they lay down a specification which must both serve their purpose and comply with international laws of warfare. This is where the term "milspec" comes from. Once the military item, built to milspec, is bought into operation by said military force it becomes a standard military pattern item. There is the CSMP (Canadian standard military pattern) and a BSMP (from our aforementioned northern cousins.) The US, (being the US) just calls theirs the standard military pattern.
In regard to a military pattern item then it has two important (minimum) prerequisites. Firstly it must be milspec and secondly it must have been in , or intended for, military service. Does this immediately make you realise that the aftermarket sporting free standing pistol grip on your AR15 does not qualify as MSSA? Yep it would appear that you didn't really have to screw that alloy bar on after all. However if you want to have a military pattern A1 grip or a military pattern A2 grip on your AR15 … sorry you'll have to get an endorsement.
- So is the Heckler and Koch SL8-4 a rifle that was built to military specification?
- - No
- Is the Heckler and Koch SL8-4 rifle that has been bought into operation by any military force?
- – No
- Does the Heckler and Koch SL8-4 rifle have a military pattern grip?
- – Clearly not.
To conclude…Is it so hard to imagine that maybe when the legislation was drafted the authors were actually trying to be as fair and unrestrictive as possible rather then being imposing and prohibitive?