You guys are starting to mix units now...and not to nitpick but I see an extra 0 above.

This from another site:

"Piezo and copper crusher (CUP) are not directly relatable due to the differences in the sensitivity of the devices used to measure the pressure with piezo measurements more accurately showing the actual pressure peak. While the relationship does not hold true for other cartridges this comparison for .308 Win shows the differences typical for CUP vs. PSI.

Comparison of Pressure Specifications Between Copper Crusher and Piezo SAAMI Specifications for .308 Win.

Copper Units of pressure (CUP) 52,000 53,300 55,300
PSI (Piezo) 62,000 63,600 66,000

I personally think/feel that for case heads over .500" in diameter one should work to keep pressures under say 60KPSI in order to minimize frame stretch, wear and tear on the locking bolts and the frame portion of the lock table...but hey thats just me.

CRICKER: Hornady and Barnes go up to 50000 CUP in their manuals.
Explain That.