I have a Remington 7 MAG..this is my primary Deer killer, its great at 400+ yards but the accuracy is changing, I have a friend with a bore scope and we are seeing throat erosion in the bullet chamber. I am sure I have shot over 3000 rounds in the last 5 years. is this a long life for a 7MAG? I know this is the second Barrel, I trashed the first barrel the first week and listaled a Lilja and we blue printed the action with tools you would use in the Aero Space work. High priced Tool and Die equipment.