One a year is when you "make" the receiver from a 60% forging.

If you buy finished receivers, you can make as many as you want.

The ATF might get pissed that you are only paying tax on the lower but how would they know?

A couple years ago you could build a FAL for about the same cost as an AR, but now that we can't import receivers, it's more expensive.

Surplus 7.62*51 was also cheaper than 5.56. If you were not worried about weight, the FAL was a whole lot more bang for the buck.

One thing that the FAL has over the AR15 is reliability. Dirt, mud, water, sand, a well built FAL will shake it off and keep firing.