I wanted to post the beginning of a "quick-view" for some of the pressures were are working with on the military rifles.
NOTE: This is NOT AN AUTHORITATIVE REFERECE! REFER TO THE FACTORY-PUBLISHED DATA FOR ABSOLUTE VALUES!!! YOUR SAFETY COULD BE AT STAKE IF YOU DO NOT HEED THIS DISCLAIMER!
OK, now that that is over
First, a brief description of CUP pressure and what that means. The short, abridged version is that a test chamber is prepared with a calibrated bore that is drilled into the chamber. A calibrated piece of copper is placed in the hole to plug it up.
The "proof" test rounds (super-hot greater-than-magnum loads) are fired and the copper plug is removed. Proof rounds are usually beyond the normal range of reloading data since they use "excessively hot" powders for a particular caliber.
The amount of expansion/stretching that the copper plug endured is measured and assigned the "CUP" pressure. "CUP" = Copper Units of Pressure. This is usually considered the maximum safe loads for a chamber, and exceeding these loads can cause metal fatigue or possibly failure of the locking mechanism.
I found the best places (so far) for published pressures are reloading reference sites. Here's what I found so far... note these are not for a particular load or powder, but the absolute largest and smallest values that are published. I would recommend more research for a particular bullet weight that is considered for a custom build.
7.62x39: 30000/40900 cup
7.62x54R: 38000/46400 cup
.308: 37000/58800 cup
.30-06: 39000/58800 cup
8mm: 36000/49400 cup
9.3x62: 38500/48200 cup
9.3x74R: 31900/42400 cup
So far, it looks like the .30-06 / .308 is the absolute hottest caliber that was built on an AK platform. 8mm doesn't seem so scary after looking at these numbers!
I'd like to see some more data to compare, because I hate using just one source. Feel free to contribute! Let's make this a larger list.