[5] In 1988, a Gun World article detailed Grennell's efforts to update the .45 ACP for the 21st century, a difficult endeavor due to the inherent design limitations of the veteran round.
In contrast, current day cartridges using modern nitrocellulose powders generating higher pressure can produce CUP in the 28,000–39,000 range.
The layout of most M1911 pistols' chambers presents yet another challenge in that the case head is not fully supported in the cartridge feed ramp area;[2] pushing the envelope in this critical area with too much pressure risks a catastrophic failure, resulting in a case bursting in the chamber.
[6] To rule out such a dangerous possibility, Grennell chose to use brass formed from the stronger and more modern .451 Detonics,[1] shortened to the overall length of the .45 ACP design.
[2] Manufacturers such as Heckler & Koch GmbH currently offer pistols rated to fire .45 Super "out of the box".