Pickup Coil/Reluctor

So we all know to keep the Gap at recommended settings (.008 on my 340) My problem is (New Distributor) I can drive the car a few month's, and then it will start getting harder to start. Then I know the pickup has moved away from the reluctor, and it's time to re-gap. My friend said try using blue loc-tite on the set screw. Has anyone ever tried this?