When I was a freshman in college I talked myself into a job helping a central CA sporting goods store reload .38 Spl. ctgs on contract for the county sheriff's dept to practice and qualify on. To save money the contract required that we use Bullseye only. Knowing that there was a possibility of a double charge from our primordial automatic loading machine (in those days about every gunshop and smith had a blown-up K-Smith of one model or another on display), we tried to develop a sampling and weighing method to detect and avoid any double charges. I kept submitting these "Cro-Magnon SPC" programs to my Biometry prof (who was after all "just" a statistician who worked on plants and animals) and he kept shooting them down. We never did get it right and finally told the dept. that either they started using a bulkier powder or we would not bid on the next contract. They refused and sure enough, the next year a K-38 blew its topstrap into the ceiling. Officer was only speckled with powder grains. Determined later that it WASN'T a double charge but a regular charge fired on top of a stuck bullet caused by a no-charge (primer just blew the bullet into the barrel throat). Too little plus just right equaled too much....
I guess the moral is double check each load with a scale and sit the bullet in the checked ctg. case neck so that no more powder CAN be put in. Very slow way to load; fortunately us retired guys have all the time in the world to go along with our dangerous short term memory losses!
