Full length sizing trouble

In my travels, one shot only works decent for me on smaller cases like creedmoore. It is junk on larger cases like o6 and up. Unbelievable the difference when using a quality lube and not one shot
Perhaps you're not coating the cases entirely?! A lot of case holder have pockets that are too deep and hold too much of the case for spraying with OneShot. (great for charging cases but not for lubing with OneShot). I have case holders I use only for OneShot where only the bottom of the case sets in a shallow pocket. I spray the case at a 45* angle first on one side then I rotate the tray and spray the other side. Using this method/angle I am able to spray inside the case mouth and also spray the entire case from top to bottom.
 
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