Since my Flattop also came with a .45ACP cylinder, it better be able to handle up to full SAAMI .45 ACP 21k psig (and even SAAMI .45 ACP +P loads at 23k).Bodyguard12, It's not really the frame size that matters ... it's the wall thickness of the cylinders, where the smaller frame flattop models have smaller diameter cylinders with thinner walls. A factory SAAMI standard 45 Colt cartridge develops about 14,000 psi chamber pressure. Experts say a flattop can handle 23,000 psi whereas a standard Blackhawk can handle 30,000 psi. Depending on who you ask, you will get different answers. If you ask Ruger, they will say to stick with SAAMI standard loads (14k psi). Some of the real 45 Colt hotrodders claim they have gone as high as 50k psi in a standard Blackhawk. Most reloading manuals that list "Ruger & T/C Only" 45 Colt loads restrict chamber pressure to 25k psi for standard Blackhawks and do not recommend anything hotter than SAAMI standard ammo for the flattops.
If you are buying a gun with intentions of running hot loads, you may want to consider buying a 454 Casull. It will shoot 45 Colt ammo just fine if you want plinkin' loads. It will also shoot 454 Cas loads that far exceed "Ruger Only" 45 Colt loads.
Well, since Linebaugh had a large frame cylinder tested which blew at 60 CUP, that's cutting it pretty fine. 25K-30K seems much more reasonable as a max ... as did Linebaugh . Me? I'll stick with under 23K as my max in both frames ... and then only for my woods load. I like to 'enjoy' my shooting, and hard recoiling revolvers isn't enjoyable no how... takes all the fun out of it ... so I will stick with 250g+ at 850-950fps for general purpose .45 Colt loads.Some of the real 45 Colt hotrodders claim they have gone as high as 50k psi in a standard Blackhawk
Eastman, the 45 Colt and 45 ACP cylinder are slightly different but I'm sure that's where the 23k psi max pressure spec came from ... 45 ACP +P loads. Some are now calling it a tier 1 load = 14k psi; tier 2 load = 23k psi, and tier 3 load = 25~30k psi.
Like buddha1percent, I had to try some 45 Colt "Ruger Only" loads just because. It only took a couple cylinders full to realize I was not having fun. I know some people are "recoil junkies" ... I used to be and I respect that other people still are . Factory equivalent loads are just fine for me now. If I feel the "need for speed", I'll break out my Super BH and shoot some full power 240gr ammo ... 6 rounds is plenty and I know the gun was designed for these 36k psi loads.