[Steve Smith]

As you said in your last paragraph, th measurements depend on individual guns. Knowing the SAAMI specs does almost diddly squat for the handloader. Our guns are so different than when SAAMI uses (pressure barrel) and so different from what powder companies use (whatever they have on hand in that caliber) that we can't ascertain much if any from their info. The best we can do is to carefully watch speeds and case performance, and stop when we feel we've pushed hard enough. Since much testing has been done on the .45 Colt case, and it has shown that the case itself will handle over 92,000 CUP before damage, it is no surprise that Linebaugh, Casull, and others have found that the case will show NO indications of excess pressure untill you're in danger of destroying the gun, or beyond that level. IOW, looking at the case doesn't help with the .45 Colt. The best you can do is watch your speed, the primer (hope it responds), and barrel condition if your bullet quality is known. Penetration tests show that the 325 to 350 grain .45 bullets reach their maximum efficiency at 1300 to 1350 fps. While they can be pushed much faster, the penetration does not increase much. These bullets at that speed should not present a dangerous condition for a Ruger or FA, assuming all is in good working order, and assuming that you use the proper powders.

These kinds of loads are about 200% of max .45 Colt PSI levels, and SHOULD get some type of ++++P designation, but the rest of the world just keeps going on like the .45 Colt is a dead cartridge.