Are traditional hunting semiauto rifles an option? If so,
Remington 742 hunting rifles (and other variants) are available in .243, 244 (6mm Rem), .280 Rem, .308 Win, .30-06
Browning hunting BAR in .243, .270, .308, .30-06, 7mm Rem Mag. .300 Win Mag
These come to mind. While they are magazine fed, the OEM magazines usually limit capacity to 3-4-5 shots depending on calibre.
Larger capacity magazines may be available from aftermarket sources. These are powerful hunting cartridges and the civilian hunting BAR is available in magnum loads including 300 Win Mag.
Unless you anticipate a need for high magazine capacity (if legal) they perform extremely reliably if sustained fire is not needed.