45Super & 45WSM case capacities
I shoot Buffalo Bore .45Supers in my 625s and Starline makes the brass
I think you could work up some Super level loads with a cast bullet and a large meplat that would surprise you.
S-L makes some good brass & their 45 Auto Rims are just as strong, if not stronger, than their 45 Super brass.
I load either case with 11.3gr/Power Pistol under a 185gr JHP with a 1.220." COAL.
That became my max load when I started working up my first loads in my Colt Govt. Mk.IV Series 70, which I modified for 45Super, because any higher would result in bulged cases in it's unsupported barrel.
I've stuck with that as my max load in all my 3rd Gen 45xxs & 325/625s too but I'm sure that load could be inched higher in these guns since they have no support issues.
Personally I've never liked cramming a heavier than standard weight bullet in "pumped up" small capacity cases, 200gr is my heaviest 45Super load.
Which, again, is why I thought a longer than 45ACP case length would be great fun for heavier loads in 45ACP revolvers & came up with the
45WSM
idea.
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The meplat on this cast Rim Rock 270gr Keith SWC-FB is .348".

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The .452" meplat on this Rim Rock 225gr DEWC-FB is the apex.
It's seated .466" deep in the case.
(That would use 69.2% of a 45ACP's case capacity & 55.2% of the 45WSM)
The 270gr SWC seats .422" deep.
(That would use 62.7.2% of a 45ACP's case capacity & 50.0% of the 45WSM)
A HDY 230gr XTP seats to just .308" deep.
(That would use 45.8% of a 45ACP's case capacity & 36.5% of the 45WSM)
(45AR & 45Super case capacities are nearly identical but slightly less than the 45ACP's while the 45WSM holds ~25.6% more
The 460 Roland holds 5.6% more than a 45ACP but can only be used in a revolver where COAL" isn't an issue.)
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