The biggest problem I perceive is the claw thingie that grabs the cartridge from the magazine and elevates it to feed into the chamber. It grabs the groove and pulls the cartridge from the back of the magazine. The leaf spring at the junction of the tang and the backstrap appears to help elevate the cartridge.
It looks like a rotating barrel lock up, similar to the Beretta 8000 series locked breech handguns. That works, so there's no question about the theory, but did they execute it properly?
The next question is the integrity of the claw thingie. This is not a good way to use steel. The claw has to be a flat piece of steel with a hook at the end. The steel would tend to fail where the hook meets the flat area.
Someone will say that 9mm extractor claws work just fine after 20,000 rounds have been fired, but that comparison is not correct. The slide moves backward with the velocity of the cartridge. The extractor has to extract an empty case, which already has inertia due to recoil. The case is moving backwards under its own force. This part has to move a loaded cartridge which does not have energy due to recoil.
A loaded cartridge has about five times the mass of an empty one. Multiplying forces by factors of five makes a big difference. Then there's the motion, which I am not going to calculate because it's late at night.
I'm interested to see how this turns out. It's certainly not the usual action design, and appears to be worth investigating. It is also noteworthy that if it works, the design could be made to ensure reliable feeding of smaller cartridges into larger chambers a la .38 Special into .357 Magnum. What the heck. They made semi autos for almost eighty years before Sig Sauer perfected them. :)
Yep. I saw the claw thing as a potential weak link too.
But there’s no reason why that claw thing can’t grab a shell from both sides with two really oversized hooks...is there?
But what is that thing way on the back of the slide? Is that an external hammer?
I just found this little footnote at the bottom of the “dynamic modelling” page.
*Designing it was not that hard - optimizing a mechanism that accelerates backward at 2000 g’s was the hard part.