Thread: Shotgun-9mm thing

Originally Posted by Toby

So my calculation is right by vc and wrong by banana? I got the measurment off chuck hawkes which is different to bananas

No doubt that I'm off with the case head measurement. I just roughly measured a 12g with crappy plastic ruler and rounded it to the nearest mm. The working should be solid though.

If you're using 0.6165" as the case head area, seems like you're including the rim of the case in the external case head measurement.
This would give you an optimistically large amount of force that the action could handle. The pressure is only pushing on the internal case head area, which is much smaller than the exterior case head area if you're including the rim.