Had a 7X57 when I was a teen ager. I believe it was Venezuelan with compensator/flash hider. Shot like a .22lr. Everyone liked it but good cheap ammo was hard to come by so I traded it. There was cheap 7mm but it was not good.
Had the same trouble later with a mauser short rifle that I liked. Only ammo I could find was from the 1920s and was fmj round nose with many misfires and tumbling flyers when they did. There were some yellow burning tracers in one bunch I got that were not marked. That was an unpleasant surprise. Seems like there is more 7X57 available now but I am off that band wagon.