Rifle Scopes Minimum Space Between Scope & Barrel?

[kwak]

This question might seem silly to someone with alot of experience that I do not have so I must ask. What is the best setup? Thanks

 

[wchartz]

If you can see daylight between the two it's OK. Don't forget the cap or cover clearance.

 

[johnsmith1775]

As long as it's not touching has always been my rule.

 

[usafabrad]

Ive seen a few shooters who have had concerns with false mirage off the barrel as it heats up because they have it so close. Easy fix is a piece of black cardboard between the two

 

[Name Enough]

I have a nice Weatherby 257 Mag and the Zeiss on top only has about .003 clearance but it still shoot .75 MOA. Of course I don't heat it up much just check sight and its good to go. So would those requirements change on a match rifle that I planned to shoot 60 to 80 rounds in a session assuming a medium weight barrel? I don't have that rifle yet but I have a bunch of mounts and I plan on marching off in that direction. This question was posed just a few days ago and the answer was just enought to see daylight. Would this hold in firing those 80 rounds over the course of an hour??