Yeah, I'd love to see some development of the 25ACP into something more potent. Longer case, more powder, as some have suggested something akin to the 22 magnum in 25 caliber.
Of course it would require a complete redesign of the 25ACP "mouse guns" we're all familiar with - with a grip frame big enough to accommodate the longer cartridge and magazine.
I'm envisioning something like a Baby Browning or even a Colt Vest Pocket with a grip frame about 1/8" wider (backstrap to front) to handle the longer cartridge and a barrel proofed to 35kPSI like a 9mm.
I would think that would get a 50gr pill zipping along at 1400 or 1500 FPS and make it into a mouse gun that roars!

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