I am about to put a 50mm objective scope on my 308.
The Leupold rings I have only leave 1mm between the scope and the barrel (which is varmint/heavy profile). You would think any gap was enough gap but I recall seeing a slo-mo of a rifle being fired and the barrel flexed at the moment of firing which would mean it hitting the scope. This will at best disturb the harmonics but more likely damage the scope, so I don't want to risk it. On the other hand I don't really want to have to buy more rings and it would mean keeping the same cheek weld/position if it works.
Am I worrying unduly? It's only a 308 after all, and I use a pretty mild load with 150gn heads, if that's relevant.