Can Anyone tell Me What This Is?

[Bruce_in_Oz]

There used to be a LOT of these floating around in Australia; I even had one.

Allegedly made from original 7 x 57 carbines. I was given to understand that they were re-bored and re-chambered for the Spanish loading of the 7.62 NATO round as loaded for their CETME rifles. As a result, the bores were VERY nice. So, allegedly not as stiff a load as, say M-80 or Oz L2A2 / F4. I suspect that the engineers were sufficiently switched to extend the freebore a little, to reduce peak pressure, but never bothered to gauge mine when I owned it. Almost as outrageous as the Columbian? FN M-98 carbines: .30-06 and 18" inch barrels! Someone in Bogota had a sens of humour.

Good scrub gun for culling feral pigs, but a bit noisy with the short barrel. (That's why ear protectors were invented). Never had any signs of hard extraction, bolt through the forehead, etc.

If the original metallurgy was as good as proper Mauser spec, (see also Swede M-96) there is no real reason for them to NOT hold up. I've seen Swedish M-96 Mausers in some serious cartridges, like 9.3 x 62 and .308Win, BOTH ex the original factory, sold under the Husqvarna label, so....

Major caveat with a lot of those early military rifles is RUST; not where you can see it, but below the "wood line". Rust pits in the metal near the chamber area can develop into stress risers for cracks if deep enough.