Originally Posted by gunsarefun
It's super simple. It's legal to own the parts. Once assembled with a block, there is no way to get an 11th round in the mag. It is permanently stuck at no more than 10. If it's disassembled it's once again a pile of legal parts.
So the classic "DA in front of a jury trying to get you convicted" scenario. DA takes a legal pile of parts, assembles the mag with the block, and now has what you had. A mag that can't take more than 10 rounds. The DA disassembles it into a legal pile of parts once again and then reassembles without the block trying to show an illegal configuration..... except that you never had it in that configuration. Not guilty, everyone goes home.
if they can remove the block from the mag without any tools I don't think it is permanent. If you can without any tools dissemble into parts then reassemble into a 30 rounder, the modification done might not and probably would not be defined as permanent. I'd rather not chance getting a felony, losing my job, and house, and possibly jail time over neglecting to pop in a rivet.