They are making solid copper bullets now but mostly for pistols in indoor ranges. They do have copper rifle ammo, mostly for the same application. The solid lead pistol bullets were leaving vaporized lead in the air of the indoor ranges.
I don’t think it would be very good for hunting though... too light for a good balistic cooeffecent in long range shooting...
And nice piles of lead dust on the ground under the exhaust fans.
Barnes X-bullets are solid copper and an excellent big game bullet. When I shoot a deer with one, it goes all the way through the rib cage and out the other side. There is no bullet left in the animal.....just two holes.