A really good Gunsmith mate of mine rebarrels a lot of ‘Roo shooters rifles for QLD shooters. He stamps a date on the underside of the barrels when he fits them. Best one was a rifle that was back for a new barrel 4 months after fitting, it had done just over 9000 rounds in 4 months. This was when Roos were worth something to shoot and conditions were good. Drought has a very major affect on roo numbers. The 223 Remington is the main cartridge now in use, with 55 grain projectiles. Even the big US projectile manufacturers will produce special “roo” projectiles, mainly just a cup and core basic bullet, that’s all you need to head-shoot Roos. They get very boring to shoot after a few hundred of them.