I often hear the advice to train with FMJ and carry JHP. It is usually followed by recommendation to shoot just enough JHP to make sure the gun feeds them reliably. But when I do the math to figure out how many JHP that would be, I'm getting a very large number.
Let's assume 0.2% stoppages (carry gun should be reliable, right?). The rule of threes says that "Given no observed events in n trials, a 95% upper bound on the rate of occurrence is 3/n".
So it looks like I need to shoot 3/0.002 = 1,500 rounds with no stoppages in order to be 95% confident that the rate of stoppages is no more than 0.2%.
Even to get 0.5% I still would need to shoot 600 rounds, and 0.5% is already crappy reliability in my opinion.
How many rounds do you shoot before concluding that the gun feeds them ok?
Let's assume 0.2% stoppages (carry gun should be reliable, right?). The rule of threes says that "Given no observed events in n trials, a 95% upper bound on the rate of occurrence is 3/n".
So it looks like I need to shoot 3/0.002 = 1,500 rounds with no stoppages in order to be 95% confident that the rate of stoppages is no more than 0.2%.
Even to get 0.5% I still would need to shoot 600 rounds, and 0.5% is already crappy reliability in my opinion.
How many rounds do you shoot before concluding that the gun feeds them ok?
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