Originally Posted by SURVIVOR619
Thanks, that makes me feel better as I recall several trips to the range using my tool to disassemble the rifle in order to reassemble a refilled magazine.
I appreciate the response.
The critical phrase in the bit you quoted is "Nut/bolt setups retaining fixed magazines"; since the weapon WOULD be able to accept a detachable magazine while the nut/bolt contraption would be loosened or removed, having 'features' at the same time is a problem.
But magazine locks such as the bullet button always operate only with a tool; there is no intermediate state in normal operation. A properly installed magazine lock of that type modifies the weapon so any magazine inserted would require a tool to disassemble it from the gun.