Permanence of 10 rd. magazine modifications

[JPB]

Just curious as to how "permanent" is defined in regards to modifying "hi-cap" mags to 10 rounds. I see a lot of rivet jobs out there which can easily be reversed with a proper drill driver and bit. Is it like the bullet button clause where if a tool is required to convert it back, it's permanent enough? My point is, since just about any 10 rd mag, given enough tooling, can be modified to hold more than 10 rounds, how dose the law interprit permanent? What's the good word?

[Shane916]

It is more the spirit of the law rather then the letter.