Heh, thanks.

Well, looking over it... I think it's a rather ingenious design for a magazine.. looks a bit clumsy, though.

Doesn't the Bizon use something like this?

Actually, they used slightly redressed Calicos in Spaceballs

and i utterly love tihs gun

one reason the gun have not sold that good was that some peoples hurt themself on the ejection port while firing, because they were to stupid to hold the gun right...
oh..and then was this (assault) automatic weapon ban...wich limited the magazine capacity for civilian automatic weapons to 10 rounds, the calico doesnt sold that well for the military and police..so the civilian market was the only one left... this stopped the calico production at all..

i would say if this one is getting produced again it would sell way better now..


and i say the helical magazine concept is maybe the most ingenious invention in magazine technology ever...the most compact high capacity magazine solution at the moment..the biggest helical mag for the calico isnt longer than a p90 50 round double stacked box magazine ...and holds 100 rounds . they look very complex, but the magazines are very durable and reliable .you can drop the magazines and kick them around if you like but I wouldnt since they cost $125 apiece.

oh..and that star wars thing... next to spaceball it was used in tons of rather bad Sci Fi B-Movies

what to hell are you talking about.... the cut away shows a half (half is a very aproximate value..) filled magazine.. they are complete full... and read next time..long as a p90 magazine with 50 rounds, but holds 100... thats not efficient?? oh..and guess how much space a regular magazine spring takes in a full loaded box magazine... thats not "efficient" either

Yes, the Bizon-2 uses a similar mag design where the magazine is placed underneath the barrel, horizontally - where it doubles as the foregrip of the weapon. It holds 66 rounds if I'm not mistaken ?

I turn 20 in a few months...



Look at this. There is a lot of space inside there that isn't filled with ammo. There is a large, solid metal axis in the middle taking up a lot of volume. If you look at the bottom left cutaway you can see large air gaps between each round. In a regular rectanguar clip about 80% (Yes, (5x-.5^2*Pi)/5x1 = 78.5%) of the volume is taken up with ammo (excluding the spring, as above):



The red area is wasted space.

It's plainly obvious to me that there is a lot more wasted space inside one of those helical clips than in one that's stacked in the regular manner.

Excuse me if I approach using a straightforward volume calculation, but I am an engineer. A simple engineering principal says that more moving parts equals less reliability.

--Scythe--

Ah,something we all much keep in mind

you sir are so wrong... the calico helical magazine is not a single stacked box magazine like you show on your paint doodle, its a double stacked 100 round box magazine, basigly spoken "wrapped" to a spiral.
and i still do not see your point of wasted space..and air... there is no wasted space inside any magazine...the "wasted" space is needed to get the used flexibility,you need to move the ammo, and there would be no other use than the one it got already....nah..maybe you could fill the wasted space with jelly...
you first have to understand the basic function of this more advanced and compact system before you can judge it.

like i said, basicly is a helical drum magazine nothing else than a regular double stacked 100 round box magazine. such a regular box magazine would be very jammy, because the magazine spring would not be able to produce enough pressure , and a stronger spring would need more space..and so on..

now replace that spring with folower, with an spring wound up spiral, wich is positionized to the side of the magazine,where it reaches inside the magazine through a opening so the spiral can grab every single round to push it upwards when it spins.

now you got a magazine with still one active moving part next to the ammo.. and the great thing is, you can use the space within the spiral for a bigger, powerfull spring, wich provides 4 times as much capacity than what you would need to deliver the whole 100 rounds into the magazine , and the space that is saved because the lack of magazine spring and follower below the ammo makes the magazine even shorter.

lets take as example the fn p90 50 rounds double stacked box magazine
on a theoretical 100 round magazine the spring would take even more space


a 100 round box magazine would have this length, just imagine it as a box magazine for the mp5:


now a straight 100 round box magazine is not the most optimized shape if you want to go cqb..... not even a cmag is very practical... you would do everything to compact it some more, to make the shape of the gun more streamlined. the goal is largest possible capacity at smallest possible space

wrapping the box magazine around the ammo transfer spiral gives the magazine the smallest possible profile, and additionaly it is getting shorter. ok..this is more a sketch, the spiral angle is not really correct, but it gives you the idea of it.



now you can see the "new" way of ammo transfer with the spiral is even more important. a magazine spring with follower would be really useless in this spiral tunnel.

but a centered spring powered transfer spiral with an follower connected to it, is able to transfer 100 rounds without getting stuck inside, in a single, smooth rotating movement, wich gets controlled by the bolt carrier.

the whole thing opened looks like that
it is very simple constructed, and reduced to the only important things.. as you can see the inner core of the spiral box is removed, only the outer structure is left as lead as a kind of "leading rail" where the ammo slides to the receiver of the gun


very nicely to see is the centered ammo transfer spiral, the part that is rotating. the whole magazine can hold ammo, because of the lack on an regular magazine spring.


the 100 and the 50 round magazines of the calico

if there is a more compact way to store ammo, that is reliable like the calico design, why it wasnt used yet? i mean..even the 30mm gau8 gatling gun is using a helical magazine, wich ammo transfer system is using more moving parts than your moped , and supports a rate of fire wich is just insane,and it does not jam...because a jam at this speed would not be really healthy.... aww..i forgot... you are an engineer

i have already worked longer in the technical development as you have possibly studied to get an engineer with your 20 years.. sorry

you have to crappy paint job me this.... you wont believe how much mechanical stress some systems create

you cant see them widely used, because noone else is alowed to sell this design exept calico.they have protected their helical magazine with several patents...
the use of it is allowed for law enforcement and military. but the military prefers way larger caliber cmags, with smaller capacity. because a 100 round helical 5.56mm magazine would be a bit heavy..and the way lighter 9mm ammo is not widely used in the army.
the police does not need such big magazines.
the use of this systems was more aimed at personal protection, concealed weaponry,secret service work...body guard crap... the only customers maybe this gun got, and the civilian ,market.

calico business didnt went so well with it. . in the four short years during which these guns were in the civilian market, perhaps 10,000 of all versions in 9mm were sold.
and then came the american automatic (assault) weapon ban from 1994,wich restricted the ammo capacity for full auto weapons to 10 rounds (also called magazine ban).
calico produced mainly for the civilian self defense market, and this ban stopped the production at all. but the patents are still protected.
kalashnikov got its own patent on helical magazines for the bizon. it was mainly used for spec naz operations first, and the existence long time a secret. kalashnikow used a very similar system, but the magazine construction is relative cheap compared to the calico, and not so durable, it loves to collect dust, and dirt.
the magazines for the calico are not aviable anymore, true collectors pieces, and peoples who own such a gun mostly say they still havent any problems with the system. even with minimum maintenance.

but if the worst should happen, and you damage your magazine, or it wears out, there is a repair service affiliated with the "unofficial Calico web page".
as of this writing, the charge is $30 plus the cost of shipping and parts. this will likely put the total cost at around $50-$100, cheap compared to the cost of replacement magazines, when they can be found.
in the early nineties, these magazines retailed for $49 (50 rounds), and $59 (100 rounds)
parts are still available from Calico, though they will no longer sell a civilian one of their magazines.
there are magazine repair kits available for the adventurous ( who does not wish to part with an extra $30)

the repair kits contain the internal workings of the magazines. there is also an outer shell kit, which contains the external parts.
so restrictive are the provisions of the magazine ban, that these parts must not be shipped, or even stored, together.
doing so would constitute a contraband magazine in the eyes of the B.A.T.F. the total cost of the parts required to construct a 100 round magazine would be around $170. this cost does not include legal fees, the cost of your confiscated gun collection, and jail time, if you are ever caught with it.

but hey..those things almost life forever

these magazines are constructed of fiberglass reinforced plastic, will not rust, and are surprisingly light and sturdy. the magazines can be stored loaded without shortening the life of the magazine spring, by releasing the spring tension.
disassembly is fairly simple, though the magazines should rarely need cleaning. loading may be accomplished by simply inserting the cartridges one by one,like on a regular box magazine or through the use of a special crank wound tool sold for rapid reloading. there is a winding crank with a folding handle located at the rear of the magazine housing on newer magazine models. it may be necessary to turn the crank a couple of times, putting some tension on the spring, to bring the magazine follower up to the feed lips.

once this is done, the rounds can be loaded against the slight pressure of the follower. as the tension of the spring increases, it can be released by pushing on a small button located in the center of the winding crank.
once the magazine is completely loaded, this button can be depressed to completely remove tension from the spring, for long term storage, while loaded. regular magazines dont like to be stored full loaded, their springs would lose tension.
with the tension completely removed from the spring, these magazines must be wound like the old Thompson style drums. this is a one time operation wich you do before storing the magazines in your magazine pouches.

50 Round Magazine 10 Turns of the crank
100 Round Magazine 23 Turns of the crank

unloading is very easy too, the magazine lips are moveable, you can push them into the magazine housing so the ammo just drops out of the magazine
these retractable feed lips make the use of a rapid reloader possible.
whatever calicos remaining stock of civilian magazines might be, it is being held in reserve. once this stock of magazines runs out, Calico will no longer be able to sell any spare parts
needless to say, the gun bill of 1994, was all but killing the Calico. there would be little point in Calico producing a 10 round version of this magazine for a new generation of post ban guns, thoughi have seen post ban, 10 round versions of the Thompson drum magazine, available for those who want the look of the classic "Tommy gun".

the Calico does not have the history of the Thompson, and there would be little call for a civilian version with a "dummy" 10 round magazine. Thompson fifty rounders are now selling for almost $700, making the fifty, and one hundred round Calico mags seem like quite a bargain.
the calico was far from the first weapon to employ the drum magazine. there is the famous Thompson drum, which also came in a 50, and a much more rare 100 round version. the Thompson has become as synonymous with the drum magazine, as it has with the stereotype of the gangster.
drum mags have been designed for the Luger pistol, the Erma submachine gun, and the Soviet PPSH used in ww2 and even viet nam. other, true, drum magazines have been produced for the AK-47, and AKS series of assault rifles, and have been modified to fit the M-16 series. all of these drums have a spring mechanism which differs from that of the Calico, by the use of a flat coil spring, which rotates an arm and lever assembly, commonly known as a "spider" to transport the rounds.
the only other weapon that I am aware of which uses a helical feed drum, is the Bizon, in 1993 Victor Kalashnikov and Alexey Dragunov, engineers of the IZHMASH JSC, located in the city of Izhevsk, western Urals, Russia, created a novel submachine gun designated BIZON (Bison). 60 % of the BIZON components are interchangeable with the AK-100 series assault rifles.

the photo shows a modification of the original snail shell magazine, made for use with the AK-47 series of assault rifles. It is shown in company with the 50 and the 100 round versions of the Calico magazines, for size comparison.



the AK drum holds 75 rounds, and it can be seen that it is much larger than the Calico mags. it is also much heavier, and, despite it's weight, much more delicate.
these AK mags are a direct development of the Soviet PPSH mag, one of which is shown with it's cover removed, in the next photo. there is a variation of the AK drum magazine which will fit on an M-16 rifle, and has been modified to feed the .223 round.
all of these drums owe their design to the 32 round "snail shell" magazine in 9mm, for the Luger pistol. this was a development for World War One, and was an attempt to give the trench bound soldier greater firepower in a smaller package.
tactically, this was the precursor to the submachine gun. this same magazine was used on the German MP 18 submachine gun, though it was later replaced with a more conventional box type magazine. the 9x19 round of the Calico, and the 7x39mm round of the AK are also shown for comparison.
the drum mag of the Thompson works on similar principles, but is modified somewhat. the Thompson drum has no feeder column, and so can only be fired in the 1928 model Thompson, and others designed specifically for it.

these weapons do not have magazine wells in the traditional sense, but use a cut out in the frame instead, with multiple locking lugs for the magazine instead of a single catch.
the Thompson drum will not fit on the later "M-1" Thompsons produced for use during World War Two, because this model lacks the cut out in the frame.
drums for the Thompson were typically of the 50 round capacity, though there was a large, heavy, and cumbersome version which held 100 rounds available.
in addition to the "true" drum magazines, a number of drum style magazines have been produced. the more common versions of these tend to be simple ammunition carriers, rather than actual magazines.
these ammunition carriers function as storage boxes for belts on belt fed guns. guns using these systems, generally feed from the bottom, in the fashion of a magazine fed weapon, rather than from the side, which is the more common method used by belt fed weapons.

the old Stoner system, along with the Soviet RPK light machine gun used "magazines" of this type. the other type of "drum style" magazine is actually a standard box magazine which has been curved sideways into a complete circle.
cmags and similar types.
the only advantage to this type of magazine is that it does not protrude as far from the magazine well as a straight version would. i am aware of only one example of this type of magazine. it was produced for the AR-15/M-16 series of rifles, and was of molded plastic.
Compared to the simple elegance of the helical design used in the Calico magazines, the other drums seem quite primitive, and crude.
these other magazines are also considerably more complicated, and delicate internally. they are also all, much harder to load,or need to be opened for loading, and then loaded in stages.

the Calico magazines, particularly with the addition of the rapid loading tool, are quite simple to charge. in addition, the more traditional drums are heavy, and their stamped metal bodies are easily dented, and damaged, and susceptible to the effects of corrosion.

uhm... the p90 for example could have the same fortune as the calico...and after it dissappeared someone could ask "..when it was that revolutionary...why there are not more weapons with toploaded sideways double stacked box magazines ?.... "