Savage 300 Chamber in Model 8 Rem 30 Barrel

[Brown Gravy]

I inherited a Model 8 from my grandfather years ago. He hunted with the gun for over 40 years. Along time ago he re-chambered from the original Rem 30 barrel to Savage 300. He just re-chambered and did not change the barrel. He shot it like that for years. I recently had a gunsmith look it over and he said I'm not sure if I should shoot the gun because the 300 Savage was .001 larger than the Rem30. Does anyone out there know if this is a problem? I know my grandpa shot it like this for several decades and took down many an elk and deer with it.