> "The problem with hand loading is that you just have inconsistent results. Some people do it very good, and some don't. What I really want to avoid is the situation where someone says, 'Look, your gun doesn't work. I'm missing, and it's your fault.' And the real issue is, well, you're missing because you screwed up the ammunition—you have it loaded too hot and it's firing too high. But you're never going to believe me!" He laughed. "I'm really not trying to make a ton of money on ammo, but I want to control the outcome and I want people to have a good experience."
I don't think it is proprietary, rather than just very repeatable. Using the company made ammunition, they can (hopefully) ensure that every bullet has the same characteristics, so it can leave the barrel at the same velocity. From the quote above, I doubt the software can compensate for different grain bullets or different amounts of powder.
http://en.wikipedia.org/wiki/Handloading#Accuracy_considerat...