JDL
NES Member
You need an FFL to work on guns for money. Or guns other then yours even for free.
I was once investigated by the state for gunsmithing without a licence. You need an FFL to engrave, plate, restock rebuild, build or paint a firearm or parts. As an example you are not even leagly allowed to pin and weld a muzzle brake on a upper for someone without a FFL even if the upper is not attached to a receiver. On the other hand if you purchase 4 loweres and make them into guns for yourself and put them into the EFA10 system and then decide you want to resell them as guns this would be OK without an FFL as long as you only personal sell 4 within a calendar year.
I was once investigated by the state for gunsmithing without a licence. You need an FFL to engrave, plate, restock rebuild, build or paint a firearm or parts. As an example you are not even leagly allowed to pin and weld a muzzle brake on a upper for someone without a FFL even if the upper is not attached to a receiver. On the other hand if you purchase 4 loweres and make them into guns for yourself and put them into the EFA10 system and then decide you want to resell them as guns this would be OK without an FFL as long as you only personal sell 4 within a calendar year.