What are the odds of success when using Burris Signature rings (inserts) on a 1" scope which is on a braked 338 RUM shooting 300s @ 2700+? Regular smooth inside rings didn't cut it. Grooved rings did not slip in the slightest when 'really' hawg'd down (nearly twisted the scope wrench off). Ring marks were quite impressive. What I'm after is the 20 MOA cant.