M-14 Magazine: AWB modified?

[103OVI]

Well, this is new to me. I have more experience with aluminum magazines than steel, so I thought I would try my luck at cleaning up an absolutely whipped M-14 magazine. While taking it apart to inspect the inside, I found something strange going on with the follower. There seems to be a small steel plate pop-riveted to the underside, causing the follower to bottom out before it reaches full capacity. I know that magazines with a capacity over 10 rounds were banned from production for civilians between 1994 and 2004, but this looks like it would have been grandfathered I’m considering it has BRW S-1 stamped on the body. Is this a “post ban” magazine that was modified to only accept 10 rounds, or did somebody just not understand what grandfathering is? Thanks in advance for looking, and any help is much appreciated.

 

[tommatt3]

Some states, such as New Jersey, had their own magazine capacity laws. NJ was 15 rounds for a time until 2018 when it was reduced to 10 rounds. There is no grandfathering in NJ.  Magazines may be permently blocked to the legal 10 round capacity.  Photo shows removal of 15 round blocks to be replaced with 10 round blocks. Note rivets.