It's only illegal to sell reloaded ammo if done so to provide for your "livelihood" (a bit of grey in that)

From the BATFE website:

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]

That being said....I would only have someone reload for me I knew well and who knew what the heck they were doing...I have loaded for 2 of my brothers off and on and my father, but won't load for a friend unless it was a pretty special friend. Too much liability...I also would never shoot anyone elses reloads except my grandfathers.