Seems to me that both systems are measuring the same thing, IE peak chamber pressure. the crusher method just has some inherent inaccuracies which the PE system avoids thus the different readings.
A German made model 95 mauser is a rather strong action regardless of what some may tell you. Pressures on US factory loaded 7x57 cartridges are kept low in deference to there still being a good number of both Remington rolling blocks & Spanish 93's around in that chambering. Yes the 93 & 95 are essentially of the same design,but the Spanish guns did not always use as good metallurgy as did the German built ones, om spanish guns were on the Soft side.
