Chilean Mausers were originally chambered in 7x57 and made by Ludwig Lowe DWM. I think that that they were very well made and are the second best of the small ring military Mausers, falling below just the Sweds in all aspects. If you don't like the cock of closing feature, the Dayton Traister cock on opening kit is an easy job for a 'smith to install for you.
That said, it is still an old rifle with an unknown history, so it would probably not be prudent to shoot hot loads in it. Stick to the recommended loads and have fun with it.
