Thread: What are you using for pressure estimation in your handloads.

A method that I have found to be useful for rear locking actions is to measure. the length of the case over a series of firings of an individual case with a chosen load. If the case stretches (and it is totally obvious with calipers) then the amount of powder in the load needs to be reduced to the point where the case does not measurably increase in length. My 'series of firings' is usually 20 shots of the same load. An example is a miniature martini rechambered to 17 Ackley Hornet with a 25gr Hornady HP bullet. The chosen load of IMR4064 gives a velocity of 3,400ft/sec and the case lasts at least 20 firings. By which time the neck is very hard which affects velocities but the case integrity is still secure.