A few comments are in order based upon the questions in this thread.
First of all, I have recently recieved a 1916 Spanish Short rifle myself, and after doing some reasearch discovered a loading for 150gr bullets with IMR3031 that should keep pressures under 40K, while providing about 2400-2500 fps. I'd have to look it up again to get the exact charge weight, which I recall being somewhere just under 40grains. The rifle could probably take a bit more pressure as found in standard 7.62 NATO charges, but I don't feel any need to puch it hard, especially when it's a short rifle that's already prone to kick back! The rifle in question had been fired by the previous owner using some .308 loads with no signs of problems, but I have heard of Indian Enfields quickly gaining headspace after shooting only several boxes of .308 and I don't want to shorten the life of my new acquisition. I'd have loaded up some rounds by now, but would first like to repair a rather lengthy crack at the tang before taking her out to shoot.
A couple other milsurp forums have sections dedicated to Spanish and South American Mausers and might be a good place to go to if anyone wants to reasearch these rifles any further. There's at least one article about the 7.62 vs .308 issue at surplusrifle.com, and certainly others.
As to the supposed weaknesses of the Mauser 93-95 actions that have been used on these guns, it should be remembered that the third locking lug that was added to the 98 action is only for the event of a catastrophic failure of the two at the head of the bolt. The earlier Spanish Mausers (pre M43, the Spanish rifle based on the 98 action) #### on closing. The 98 is also better equipped to direct gases away from your face in the event of a case head separation, but if you make it a habit to wear eye protection whenever you shoot these, that should suffice. Similar questions have been raised about the many Turk Model 1893 Mausers that were imported years ago, though with the caveat of always wearing eye protection and avoiding really hot loadings, they seem to be providing people with lots of range time without any problems. The question also comes up alot around the Swedish M96 actions, though I'm not sure if they have some extra venting ability when it comes to ruptured cases.
If you have a Spanish Mauser in the original 7x57 chambering, then you are a lucky person, since that's a really nice cartridge, at least by all of the accounts that I've read about them (it's one that I don't have).
Spanish and German M93 Mausers in 7x57 were really cutting edge weapons in their day, inflicting heavy casualties on the American troops in Cuba and the British in South Africa. Their slick bolt action, stripper clip loading and flat trajectory of the 7mm Mauser gave them a decided advantage over the Trapdoor Springfields, Krags and early Lee Enfields that lacked a stripper clip guide. The last time I saw a 7mm Chambered Chilean M95 for sale, the asking price was alot more than a typical Mosin, or what a Lee Enfield would have gone for a couple of years ago.
There's my two cents!
Frank
When I get home Sunday I'll take it out and get some photos... wish I could remember what model it is. I feel like a bad gunnut 
