Quote Originally Posted by Bruce_in_Oz View Post
If your K-31 barrel is shabby and you cannot find a NOS replacement, any good gun-plumber could run up a replacement in blued or stainless. I might cost more than a whole new K-31, but them's the breaks.

The only other caveat is rim size. the smaller diameter of the .308Win rim WILL cause a certain amount of annoyance because of ejection "failures". I had similar issues with my K-11, using .284Win brass, before all that Serbian stuff turned up.

A little "adjustment" of the travel of the extractor improved it, a little, and it was OK for "slow-fire" matches. Rapid? Not so much. Converting to .308Win without altering the bolt-face AND the extractor is fraught with adventure.

If your barrel is in good condition, just stick with the original cartridge. The biggest challenge, then, is to find a source of GP-11 bullets or a similarly profiled bullet. K-31 barrel have short throats and Sierra Match Kings are a problem because of their tangent ogive. You could get that friendly local gunsmith to CAREFULLY lengthen the throat do accept 168gn SMKs, or similar, or find a bullet with a secant ogive.

Cheers from Oz.
You could set the bullet further back in the case. Lecac on youtube is the best Swissicon K31 loader I know of.