Jack O'Connor wrote of many of these guns sold to Mexico and other south of the border countries prior to the adopting of Mauser design ('93, '95, etc.). Remington was pushing for the military contracts hard. Named often Remington Ryder Rolling Block rifle. (Mr. Ryder the designer as I understand). At one time they sold for about $25.00 a dozen (yes, 12) surplus. Jack recommended keeping the loads at the "starting load" level in the current manuals of 50 years ago and the 7x57 was held down for the abundance of 93 Mexican Mausers that replaced the Rolling blocks. Interesting piece of history. Not unuseful in the field if you don't get wild with loads but "plus P?" NO!!!! Luck. Happy trails.