According to USC (United States Code) you can buy a firearm for him and gift it to him so long as you are not receiving money in exchange. You must also know that he has a clean record without any criminal charges, does not use illegal drugs, is not an illegal alien, has not been dishonorably discharged, etc. You can read more in Title 18 of the code, chapter 44, section 922, specifically parts (b)(1) and (d).
On a side note, he would be able to purchase a firearm from a private owner on his own, which may be a smarter option as it eliminates you from the loop and absolves you from any responsibility.
As far as I know, there is no way to have you purchase the firearm but have it under his name. That is in essence a straw purchase and is illegal. If you gift the firearm to him, the registration and paperwork will still be under your name.
On a side note, he would be able to purchase a firearm from a private owner on his own, which may be a smarter option as it eliminates you from the loop and absolves you from any responsibility.
As far as I know, there is no way to have you purchase the firearm but have it under his name. That is in essence a straw purchase and is illegal. If you gift the firearm to him, the registration and paperwork will still be under your name.