Actually... You were informed that you were putting yourself at risk.
Now, I read that as selling your ammunition is a no-no... I would hope that if I did something stupid that could potentially put me at risk of breaking a law that someone would notify me about it so I could correct my error. In fact I have received friendly messages in the past like the one I sent you and unlike you I appreciated the heads up. Also, as a reloader myself I'm not about to sell my reloads to someone else and risk the liability should something go wrong. I'm confident in my measurements, etc but it only takes one mistake.Q: Is a person who reloads ammunition required to be licensed as a manufacturer?
Yes, if the person engages in the business of selling or distributing reloads for the purpose of livelihood and profit. No, if the person reloads only for personal use.
[18 U.S.C. 922(a) (i) and 923(a), 27 CFR 478.41]