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Should a scope be sitting tight in the scope mount?

A Shooting Times reader was concerned about his new scope being too tight in the scope mount. Bruce Potts had some helpful advice.

scope mounts

A steel bar pushed through the scope rings, with a bore paste, will ensure that your scope fits perfectly

A reader asked this question about tight scope mounts: I have fitted a new scope to my .243 stalking rifle and it is very tight in the scope mount. Is this right? I don’t want to over-tighten and damage the scope’s body.

Shooting Times’ rifle reviewer and stalker, Bruce Potts had this advice: One of the most common causes of damage to a scope is that of poorly made or misaligned scope mounts. Not only can they cause external damage by denting the body of the scope, they can also squeeze the internal mechanism. as a result, your scope won’t function properly and it will also lose value.

This can be easily rectified with the aid of two simple bars of steel (“steel fabricators”, which you can find by searching online), one with a 1in diameter and the other with a 30mm diameter, and some grinding paste such as J-B bore paste or uSP bore paste. Place the correct-sized rod into the scope rings as you would with a normal scope and apply the paste.

Push and pull back and forth slowly, reapplying paste as necessary until it is smooth, while slightly tightening the scope screws to keep an even pressure. remove the bar and degrease with gun Scrubber, Kg-3 or a similar type of product and you will see the uneven areas are smoothed to a shiny surface. Your scope should now fit perfectly.