There are a lot of good choices out there.
He should determine the following first:
(1.) How much is he willing to pay for the rifle.
(2.) How much accuracy does he need in the rifle.
(3.) What are his maximum Range and Penetration Requirements.
(4.) What is the maximum weight requirement for the rifle.
(5.) Does he only want the rifle chambered for 7.62 NATO or 5.56 NATO ? Or is he willing to go to a non military factory cartridge ? Or is he willing to have it chambered in a Wildcat cartridge ?
(6.) Does he want a Semi-Auto or a Bolt Action Rifle.
(7.) Does he want the rifle to be a Single Shot (stiffer receiver and greater accuracy) or does he want it to have a magazine.
(8.) Does he want the rifle to have a detachable magazine or internal box magazine.
(9.) What is the largest game animal does he want to use to rifle for ?
There are so many variables to consider.
Here are some examples of rifles.
If Accuracy is the number one priority and price is no limit. Then a custom rifle built on a Hall Giant Action, with a Lija Barrel would be a good choice.
If he wants to have a very good Repeating Bolt Action, then a custom built rifle based on a Remington Action would be a good choice:
Jarret, Chandler make good rifles.
If he wants a Cheap but Accurate Factory Rifle:
Tikka, Savage make Excellent (Ugly) but very Accurate Rifles right out of the box.
Some good cartridges: 6.5-284 or 6.5-08(a good medium range wildcat), 30-338 Weatherby (a good long range wildcat).
338 Lapua (a very good 1500+ yard cartridge)
Factory Cartridges to consider:
.223 or 22-250 or .243 or .257 Roberts or 257 Weatherby (good short range cartridges for small game)
6.5x55 Swedish, 7x57 Mauser, 7-08 (good medium range cartridges out to 800 yards. Good for deer and pig).
7.62 NATO (a good cartridge out to 800 yards)
The Great 30-06 (probably the most widely available cartridge. You can be in some little town in the middle of now where and still be able to get ammo. This is good for out to about 900 - 1000 yards). Both 7.62 NATO and 30-06 are good Deer Cartridges.
300 Win Mag (a good 1000 yard cartridge)
7 mm Rem Mag (Another very good cartridge out to 1000 yards).
.338 Win Mag (Good long range cartridge, Good for Elk).
.375 H&H (Good for Anything in North or South America. Offers Great Penetration, Ammo is widely available.) Will kill anything in Alaska, Canada or the Continental US.