IMHO reboring hasn't effected the collector value. It was done along with thousands of others when Spain decided to use the 7.62x51 as the basic design for their CETME rifles. It's quite possible the Spanish police ordered some of these for themselves but maybe they were just issued with them for uniformity of cartridges for issue. They converted a lot of their old 93/95 Mausers to 7.62x51 CETME. Some of them were carbines and as often as not they used the original stocks. Many can be found with new unfinished replacement stocks and as seen with the OPs polished metal I have one that is identical. They also converted rifles to the 1916 and FR7 configurations. This IMHO just adds to their history and they are completely acceptable and correct. These are fine/handy little rifles and they are quite accurate as is.
Spanish Mausers have seen a lot of action during their civil war. Reboring/rechambering them to the 7.62x51 CETME cartridge was a very good stop gap for Spain until enough CETME assault rifles were available and in the interim it allowed their troops/police to become familiar with the cartridge and what it could do.
The CETME cartridge is dimensionally identical to the 7.62x51Nato or 308Win. That being said, the CETME cartridge is loaded with a 112 grain, .310 diameter boat tail bullet that has a plastic core in its nose and lead core in its base. It is loaded to the same velocities as the 7.62Nato but supposedly pressures are lower.
There are a lot of people here claiming that these lovely/handy little rifles will handle the 7.62x51Nato cartridge without issues. Personally I disagree. I have seen three of them KABOOMED while shooting surplus 7.62Nato ammunition. The only conversions I would personally trust to shoot this ammo are the FR8 models which were built on 98 type Spanish actions.
Here's where the confusion comes in. The 112gr bullets loaded into the CETME cases are very long for their weight and actually longer than some 308fmj boat tails available. They are also in a very low drag configuration with long ogives. They are also extremely accurate. I purchased a couple of thousand of the CETME pulled bullets and powder from SFRC when it was available. They work well in my 7.62x39 bolt action and well in Mosins. Of course they also work well in the Mausers.
IMHO these rifles in excellent condition inside and out are valued at $500+ in 7.62x51CETME. When they can be found in 7x57 with perfect bores etc they are slightly more valuable say $600+.
These rifles used to be fairly common. Once in a while they show up at gun shows but usually in fair to good only condition.
I have told you my experience with these rifles. Google them and look at the pics of other KABOOMS using commercial 308Win and surplus 7.62Nato. Be careful if you have one and want to shoot it. Your rifle may or may not handle the standard Nato or commercial loads. Your choice, your rifle.
