z1 - I can't help with the documentation you're looking for, only what I use to stay within the realms of safety. First off, stay reasonably close to current published data and you'll probably be alright. I say "reasonably close" because all you have to do is compare load data from 5 years ago and you will notice some slight changes.
I use a combination of primer appearance, felt recoil, heard report, bullet velocity, case extraction, and CHE measurements. Take note I said "a combination of". Each of these things don't tell you a whole lot about pressure by themselves, but together they willl lay out a pretty clear picture. Keep in mind, these things will not tell you how much pressure you have - you'll need to invest in a strain gauge for that purpose.
I tend to base what I am looking for off results of factory loaded rounds as well. Factory rounds will be somewhere close to max loading for a specific caliber, giving you a pretty good idea as to where your handloads are at.
Say you have a 35 Remington on a Contender frame that pushes 200 grain bullets at 1777 fps, a moderate recoil (for you), cases come out of the chamber easily, and CHE measures at .0003" above the measurement you took on an unfired round. You shoot a few handloads, and with a 41 grain charge of W748 have a velocity reading of 1820 fps, a heavy recoil, cases that have to be pushed out with a cleaning rod, and .0005" CHE you can pretty much guarrantee you're over max pressure.
If you look at those specs hard enough, you'll see that you probably hit max at 39.3 grains with a Hornady roundnose. wait........I didn't mention what bullet we were shooting...........exactly, ;change components you have to go back to the beginning and start all over.
Pressure signs can be a big discussion in a group of handloaders, as can velocity to determine pressure and CHE to determine pressure. My take on it - watch for as many things as you can and you'll enjoy many more days at the range.
PS - If the above photo was of the 444 rechamber, I don't think the true story ever came out, or if anything was truly resolved in the incident.
