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paradox
11-11-2006, 11:58 AM
So I was browsing through the US patent database looking for when Armalite’s AR-10 patents ended when I found this interesting patent:

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=1&f=G&l=50&d=PTXT&S1=Armalite.ASNM.&OS=AN/Armalite&RS=AN/Armalite

It is a design on how to make a high pressure rimfire cartridge that mirrors the abilities of the standard centerfire cartridges we all know and love.

Here are a couple of resized images from the patent application showing a standard rimfire cartridge then a sample of their new idea:

http://img401.imageshack.us/img401/9679/rimfirebx1.jpg
http://img484.imageshack.us/img484/1993/newammopt8.jpg

I can’t see how anyone could define this as a centerfire cartridge, thus any firearm chambered for this ammo wouldn’t be covered by SB23. Does anyone have contacts within the industry where we can get ahold of an Armalite suit to tell them how much money they can make just in California from upper and ammo sales?

ETA:
The most popular cartridge used when firing a firearm is the .22 caliber rimfire cartridge. Rimfire ammunition is often used because it is relatively inexpensive as compared to center fire ammunition. Thus, rimfire ammunition allows greater use of the firearm with less cost for such activities as recreational shooting, weapons training, hunting, and the like. Rimfire ammunition may also be used with firearms that conventionally fire more expensive ammunition, such as military weapons. These types of weapons may be adapted to fire the lower cost rimfire ammunition during training exercises with the firearm, thus saving on training expense.

One example of a rimfire cartridge is illustrated in FIG. 1 and designated generally at 10. Rimfire cartridge 10 includes a bullet 12 connected to a casing 14 at crimped portion 17. Opposite bullet 12, the casing 14 has a rearward end member 16. Casing 14 also includes a wall 22 having an inner surface 22a and an outer surface 22b. Wall 22 and end member 16 define a hollow interior 24. Projecting radially outward from wall 22 and extending between wall 22 and end member 16 is annular outer rim 18. Outer rim 18 defines an annular pocket 20 communicating with hollow interior 24. As is well known in the art, when the cartridge 10 is manufactured, a quantity of fluid priming composition 28 is spun into annular pocket 20 and allowed to dry. A quantity of powder 26 is then placed within hollow interior 24 of casing 14. In order to fire the cartridge, a firing pin configured to sharply strike casing 14 at outer rim 18 crushes the priming composition in annular pocket 20 which in turn ignites powder 26. Powder 26 burns rapidly and creates gas as it burns. The pressure from the gas forces bullet 12 from crimped portions 17 and propels bullet 12 down the barrel of the firearm.

One of the drawbacks with such rimfire cartridges is that casing 14 suffers from low strength and is prone to failure, particularly at rim 18, when casing 14 is used for a high velocity cartridge. Thus, even though the capacity of casing 14 can hold a sufficient quantity of powder to produce a high pressure cartridge, casing 14 will fail due to the higher pressures generated by the larger quantity of burning powder. This results in less powder being used with the cartridge to minimize the risk of casing failure. The reduced amount of powder causes less gas pressure to be generated by the burning powder. This in turn lowers the velocity and the energy of the bullet when it is fired.

Center fire cartridges are popular for their ability to generate high bullet velocities. However, center fire cartridges can be expensive and difficult to manufacture.

There remains a need for cartridges which effectively addresses the problems of casing strength, expense and manufacturing difficulties associated with prior art cartridges. The cartridges should be capable of use in existing firearms with minimum modification to its components, and the cartridges should have application with all caliber firearms. The present invention is directed towards meeting these needs, among others.

VeryCoolCat
11-11-2006, 12:07 PM
The ammunition/firearms would probably be very costly.

AJAX22
11-11-2006, 12:21 PM
I wonder how that would handle high pressure loads? additionally wouldn't the rim hinder magazine loading and reliability?

If a rimfire cartridge could be developed without a rim (think a magnum .25 acp without a primer) that could handle high pressure loadings it would probably be popular here in the peoples republic. however you would not be able to reload it, and it would be very expensive.

paradox
11-11-2006, 12:21 PM
The ammunition/firearms would probably be very costly.

Maybe, but there is a good chance they won't. This is Armalite we're talking about, they do have skill in cranking out high quality firearms at a reasonable price. I doubt an Armalite pseudo-rimfire upper would cost much if any more than an Armalite centerfire upper. As for the ammo, the genius of the patent lies in making ammo cheaper. It is cheaper to manufacture rimfire than it is to manufacture centerfire ammo on a large scale. They could start out by matching the price of standard centerfire ammo and still make a pretty penny. Once California dollars prime the pump and get the assembly lines running, the ammo could wind up being cheaper than the cheapest centerfire.

M. Sage
11-11-2006, 12:48 PM
I wonder how that would handle high pressure loads? additionally wouldn't the rim hinder magazine loading and reliability?

Rimmed rifle ammo works in magazines. Romaks and Dragonevs (for example) use a rimmed cartridge and are mag-fed. I know they're not semi-auto, but many bolt action repeaters used rimmed cartridges without any loading or feeding problems.

With the thicker walls on the case, it looks like it'd handle higher pressures just fine.

paradox
11-11-2006, 01:35 PM
I'm also not sure that this type of case needs to be rimmed. It may be possible to make a rimless version that still isn't "centerfire". I doubt that Armalite filed this patent without doing at least a bit of R&D proving the viability of the idea. The patent was only filed two years ago, so things could be actively moving within the company. Perhaps a little nudge from Californians could actually bring this to fruition and commercial availability. If any company could pull it off it would be someone like Armalite.

NeoWeird
11-11-2006, 06:05 PM
The correct answer is to create a primered round similar to a center-fire that has a donought primer instead of a round primer. Thus it would be a eccentric fire round instead of a center-fire primer round.

Imagine Berdan primers where the point of impact is above the flash holes instead of the center of the primer.

m1371
11-11-2006, 09:47 PM
The ammunition/firearms would probably be very costly.

Not necessarily.

There would be the initial investment required to get it up and running, but when you start to look at the long term the payoff is there.

Take a step back and look at the larger picture instead of expecting instant gratification out of it. A company as large as Armalite doubtfully would go into something like this all by themselves, much less without being realistic as to the overall profitability of something like this.

Get one of the major ammo manufacturers onboard and it wouldn't be very costly at all.

It's just a matter of selling the viability of the option to everyone concerned.

mblat
11-11-2006, 10:27 PM
Most important question here this:

does anybody really belive that Arnold will veto AWB bill that includes word "rimfire"?

RANGER295
11-12-2006, 12:39 AM
Most important question here this:

does anybody really belive that Arnold will veto AWB bill that includes word "rimfire"?
Lets say that they do ban that after we have built up all of our OLL’s with this. After we register them as AW’s we may be able to build them up in any way we want to?? Or would it be like AB-50 where you couldn’t register an AR lower with a .50 BMG upper and then convert it to .223? Either way I would buy one as long as it isn’t to through the roof.

hoffmang
11-12-2006, 01:54 AM
That would all depend on some new legislation that doesn't yet exist. I know lots of you think I'm wrong for saying this but I don't think we'll see legislation that it this far reaching anytime soon. Dems at all levels have learned that more serious gun regulation has potentially large impacts on re-electability.

-Gene

klmmicro
11-12-2006, 06:34 AM
That would all depend on some new legislation that doesn't yet exist. I know lots of you think I'm wrong for saying this but I don't think we'll see legislation that it this far reaching anytime soon. Dems at all levels have learned that more serious gun regulation has potentially large impacts on re-electability.

-Gene

This si the same argument that has been heard regarding the current OLL situation. If they change the rules, there must be a registration period opened? Says who?

For the powers that be, it would be nothing to add the "rimfire" line into existing legislation and then just let it be fought in court. The other side is that they simply ask that new legislation be drafted to counter the new threat. While full bans are unpopular and costly for libs during elections, they have and do successfully argue that AW's are evil. No-one lost their re-election bid over the .50 cal ban...you cannot rely on the voting populace of this state to present clear risk for banning actions.

The expense to develop the new round and bring it to market is not realistic in the end. There is already an option (centerfire) that is proven reliable. My opinion only, your mileage may vary.

mblat
11-12-2006, 09:17 AM
That would all depend on some new legislation that doesn't yet exist. I know lots of you think I'm wrong for saying this but I don't think we'll see legislation that it this far reaching anytime soon. Dems at all levels have learned that more serious gun regulation has potentially large impacts on re-electability.

-Gene


This argument MAY apply in central/eastern/southern states.... Not in California....

metalhead357
11-12-2006, 11:14 AM
Let us not forget too...with each day more OLL come into the state & each and every day whereby nobody is arrested and nobody does anything illegal with them works in our favor. What? day 300 of 2006 and 30,000+ OLL's in state.... them numbers are hard to overlook. The dems would be stooopid to be unmindful of that.....

RANGER295
11-12-2006, 01:02 PM
I just thought about another possible side affect of this. If it results in a rimfire AWB, then all of our 10/22’s and other such guns with evil features would be AW’s. I don’t know if it would be worth losing that. The OLL thing is kind of a pain but not that bad. I could live with that if that was what was needed to keep my .22lr toys off of a list.

hoffmang
11-12-2006, 02:14 PM
klm:

Says the US Constitution. The fact that Due Process and Takings would be major problems where why the legislature came up with registration in the first place. DOJ had one and only one way to cause registration and that was to update the list by one of the two methods available to them. Change the regulation at the DOJ doesn't create a registration period and thus it will probably cause the rulemaking to fail.

Those regulatory issues aren't there if the legislature passes new law. However, that new law does have to be Constitutional and the only way that these bans have been able to stay Constitutional (though ignoring the 2A) has been to allow registration of weapons that are in the future illegal to possess. It is the basic concept of the Constitutional ban on Ex Post Facto law that you can not become a criminal for owning a previously legal firearm.

-Gene

Scarecrow Repair
11-12-2006, 03:53 PM
It is the basic concept of the Constitutional ban on Ex Post Facto law that you can not become a criminal for owning a previously legal firearm.
Out of historical curiousity here, how does this relate to the 1934 National Firearms Act? I just read the wikipedia page http://en.wikipedia.org/wiki/National_Firearms_Act on that, and it is short and somewhat unclear. It does say it was a tax law, not a plain ban like today's CA laws. Was that a way to get around the takings clause, and if so, what is to prevent something similar today to slow down the proliferation of evil rifles and guns? What happened to people who already owned the? Were they inheritable? It says the original $200 transfer tax was roughly 5 months salary; that seems exagerated to me, but an inflation calculator says that $200 is only $2854.86 today.

hoffmang
11-12-2006, 05:10 PM
The '34 NFA act said you needed a tax stamp to transfer but not simple possession. Anyone whose state will allow them only needs a sheriff's signature to own a fully automatic as long as they pay the transfer tax. No takings, no ex post facto, no due process issues.

It still may not meet the Second Amendment as there has never been a test case fully adjudicated. US. v. Miller was remanded and wasn't about automatic weapons at all.

-Gene

-Gene

RANGER295
11-12-2006, 05:16 PM
Out of historical curiousity here, how does this relate to the 1934 National Firearms Act? I just read the wikipedia page http://en.wikipedia.org/wiki/National_Firearms_Act on that, and it is short and somewhat unclear. It does say it was a tax law, not a plain ban like today's CA laws. Was that a way to get around the takings clause, and if so, what is to prevent something similar today to slow down the proliferation of evil rifles and guns? What happened to people who already owned the? Were they inheritable? It says the original $200 transfer tax was roughly 5 months salary; that seems exagerated to me, but an inflation calculator says that $200 is only $2854.86 today.
Doesn’t this sound a lot like the poll taxes that were ruled as unconstitutional because the discriminated against minorities?

WeThePeople
11-13-2006, 12:21 PM
klm:

It is the basic concept of the Constitutional ban on Ex Post Facto law that you can not become a criminal for owning a previously legal firearm.

-Gene

Then why are pre-ban non-registered owners arrested?

hoffmang
11-13-2006, 12:27 PM
Then why are pre-ban non-registered owners arrested?


They were given notice under Due Process and an easy path to follow the law. There is a purist argument that they have a challenge there, but its not strong. Ignoring the 2A, a rational basis test shows that all you had to do was send in a postcard after DOJ advertised and posted notices. Again ignoring the 2A, government can on a rational basis, compel you to register things.

-Gene

Bizcuits
11-08-2007, 11:38 AM
The ammunition/firearms would probably be very costly.

my future kids don't need college as much as I need a nice ar15 with evil features and detachable mags.:chris:

Bizcuits
11-08-2007, 11:44 AM
Then why are pre-ban non-registered owners arrested?

They aren't. In Sept of 2001, my brother commited suicide with my fathers MAC90. It was purchased in 1996, but never registered. LE confiscated all of my fathers guns, ran them, then happily returned them.

chico.cm
11-08-2007, 03:04 PM
Bizcuits,
My condolences to you and your family.
However, I am glad that LE did not confiscate your weapons, adding insult to tragedy.

stator
11-09-2007, 06:33 AM
So I was browsing through the US patent database looking for when Armalite’s AR-10 patents ended...

In about ten years, eh. The patent number is 5,638,626.

Shane916
11-09-2007, 05:16 PM
You gentleman do realize this thread is from November... of LAST year? :)

paradox
11-09-2007, 05:26 PM
You gentleman do realize this thread is from November... of LAST year? :)

Yep. It got bumped because I linked this thread in another thread that said high pressure rimfire ammunition was impossible.