I came across this rifle the other day in one of my online haunts. I'm not overly familiar with the various Mausers out there. What are your thoughts on the Spanish Mausers in 308? Anything particular to avoid or favor in them? The intent is to sporterize it into a shooter.

Seller's Description:

FS/WTT: Oviedo Spain M1916 - SAMCO MIA FL 308W "Spanish Mauser"

Technically 7.62x51 Nato, but stamped 308w - shoots both fine. Rifling is good, 21" bbl, turned down bolt handle, 5rd mag, iron sights, imported by SAMCO during the mid-1980's. No chips or cracks in wood stock, great looking Mauser, the cell pics don't do it justice. Guns & Ammo Magazine featured this rifle and had it tested by HP White Laboratory Inc with a variety of commercial saami spec 308w loads. The rifle shot great and they tested it to destruction, only after reaching 98,000psi. Thus safe for 7.62x51 and commercial 308w ammo.

Crickets?

Yep; very familiar with them and other Mausers. Avoid these like the Corona. These were originally 7x57, operating at a pressure of about 40K psi. The Spanish rebarreled them to 7.62 CETME; NOT 7.62 NATO!!!
The CETME cartridge operates at much lower pressures.
The importer stamped them 308; they aren't.
Whilst they certainly will take high pressures, as your test indicated, it does not tell you that the receivers can be soft and will set back with sustained use of commercial or Nato ammo. If you are really set on getting it, I would use light loads, or just shoot it until the lugs set back, then throw it into the trash.
You didn't say the price, but you can get a 98 Mauser in 308 for $400 or so.

Yep, what he said. M1916 Spanish Mausers are arguably at the very bottom of the heap.

They are fine in 7mm and 7.62 CETME, but not when fired with 308 or 7.62 Nato. Good thing is that they are soft so will fail slowly; not fracture. The bolt will be very hard to open before it gets too dangerous.

Appreciate it guys, they were asking 350 but I believe I'll pass.