The OP is 100% correct (in his choice of title).

Now then, why would a manufacturer of ammunition go to all that trouble and put a "NR" on their factory made product...? Along with a warning about use in carbines?

Perhaps because the components were never designed to reliably and safely function more than once? Kind'a like baby wipes?

Never doubted that it could be done: best of luck to those who choose to do so!

FWIW, 4.6gr Bullseye (the LEE #0.5 Scoop) is a favorite 9mm load for me with a number of different bullets.

Cheers!

P.S. In my (very limited) reloading experience I've seen one case failure: that was more than sufficient and as a result I further refined my reloading's virtual regimen.