If you insert a magazine that holds more than 10 rounds, then it does.
I believe that 922r applies as soon as the rifle is capable of accepting full capacity mags, but definitely once a mag is inserted.
Yeah, it sucks.
Edit: You know, I went back and reread 922r, and there is a good chance that I am talking out of my ass again. 922r doesn't mention hi-cap mags as part of the criteria of needing to meet it. It just says that if you build or assemble a semi-auto rifle...
It does say that if you replace or add ANY part, then you need to comply. The bullet guide is not considered a 'part', so it may not drive you to compliance.
A magazine definitely would.