Initially launched in 1955 as the model 740A, the firearm was rebranded in 1960 as the model 742 and became available in multiple calibers, including .30-06 Springfield, .243 Cal, .308 Cal and .280 Remington. It was produced in various deluxe and presentation grades. We produce an oversized 10-round magazine compatible with the aforementioned calibers. Please note that this magazine does not engage the slide lock on the final round for the 7600 series rifle. It is compatible with the new model 750 but similarly does not engage the slide lock on the last round.