Posted on 07/29/2008 7:23:14 PM PDT by mamelukesabre
A Revolution In Cartridge Feeding
The Boberg XR9 Introducing the world's most powerful 9mm pocket-sized pistol.
Summary
Basically, the XR9 is a pocket pistol with a full length barrel, having the magazine located directly under the chamber. The patent-pending feed mechanism grabs a cartridge from the magazine and delivers it straight into the chamber. This allows the chamber clearance to be significantly less, causing less energy and noise to blast out the back. With this combination, kinetic energy is maximized, and in many cases will exceed the energy produced in full-sized pistols.
Just an FYI to all of you out there that prefer other calibers to 9mm - be patient! The first offering will be in 9mm because it remains highly popular, is relatively inexpensive to practice with, provides a decent round count in the magazine, and delivers a lot of power in many styles of +P. The key point here is that the Boberg XR9 will always provide superior power to any same-sized gun, and many larger guns in any caliber it is offered. Other calibers will be offered pending the success of the 9mm version.
(Excerpt) Read more at bobergengineering.com ...
“Both” is always a good answer.
Look at post 13. It appears to me there is an extractor machined into the slide...not a separate piece with a spring, but just a little hook in the slide.
Maybe. Hard to tell.
The empty appears to be bumped out of the way by the new round.
Or did you mean to say “...not thrilled about it not having an ejector...”?
btt
Kinda like a bullpup in a pistol............ BTW, no apparent feed ramp.
i don't see an ejector, so i hope there's something there i missed. it truly is an innovative design and i hope it works out for them, but i'll have to wait till several thousand production guns are on the market and reviewed before i bet my life on one.
There is the key question. I also carry a P3AT (Or a S&W 637, or XD-45 depending). If this thing cost $600+ I'll stay with the Kel-Tec. It also weights twice as much as the P3AT, heck it weighs more that my 12+1 9mm P-11.
It would be more accurately compared to the P-9, a single stack 9mm from Kel-Tec.
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. :)
The Judge comes to mind ..... .45cal and .410 in a pistol ...
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.
An external hammer makes sense. There’s not much room for a sear to release a striker like in a Glock. The feeding mechanism is in the way. You could build a sear that reached over the feed area and make it in a U shape, like the 1911 trigger bar. This would make it rigid on both sides, but it would be an expensive part. The hammer is a proven mechanism, and this thing has some radical ideas. If I thought of it, I would want to use established methods wherever I could so that any problems would be easy to isolate.
If you want a proven pocket 9mm that has been sold for several years to the most discerning buyers, check this out:
www.rohrbaughfirearms.com
Of course, it’s not cheap. But after you empty our wallet, there will be plenty of room in your pocket for a pistol.
But it all depends on what your life is worth.
bfl
A somewhat different variation I've pondered would be a long-recoil operated pistol, in which the barrel and slide can travel rearward for about the length of a cartridge; after that, the barrel would slide forward, then a cartridge would pop up, and then the slide would push the cartridge into the barrel. When ready to fire, the barrel would be completely forward of the grip, but in 'carry mode' the barrel could be locked rearward.
Methinks their claims of “higher power and increased kinetic energy” will prove to be greatly exaggerated. Internal ballistics of like cartridges in like chambers tends to be, well, alike. The method of feeding will not have an appreciable effect upon the firing sequence, pressure, etc. The cartridge obdurates and seals to the chamber walls well before peak pressure is reached, so the blurb about escaped gas or pressure is poppycock.
I’m not saying that a shorter action is not a good thing, but their performance claims are bizarre.
Minor bbl length differences will not achieve the performance increases that they claim.
Are those roller bearings in the slide?
Never mind...spring
Mine's tucked away for some lucky collector one day...
Bump for later.
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