110 Round "Rotary Magazine"

[Kilibreaux]

Well it's finally HERE!  Woo HOO!

As I type this I am looking at my new 110 round "rotary magazine" just arrived from Cope's Distributing!  Order quickly my friends...

[Madhouse]

Awesome!  Looking forward to hearing how your first range trip goes!

:thumb:

[Microgunner]

You know the rules. Without photos it doesn't exist.  :ttiwop:

[SnakeWrangler]

I mentioned this on another thread, but it is more relavent here. Just got my 110 rd mag last week, but one thing drives me crazy about it. The rattle. Trying to figure out a way now to put an end to it. Any suggestions?

[Kilibreaux]

Do you mean the "rattle" after it's loaded?  If so then the short answer is no, there's probably nothing you can do except maybe cobble up some sort of external enclosure like a soft, padded bag that would provide both protection and noise dampening.

UNloaded the only thing moving around inside are those tiny plastic bullet "placeholders" that ride on a nylon strip so those can't be making much noise.

[Kilibreaux]

I haven't gotten around to it yet but I plan to fabricate a padded drum carrier.  The idea is to provide impact protection for the drum body through a closely fitted case and the drum will be usable with the padded case in place.  Another benefit will be keeping out dirt and debris, and finally, the case will have its own QD fittings so it can be clipped on to a belt or pack.

My initial thought was not to make the padded case so the drum can be loaded while inside, yet it occurs to me I can add a velcro "window" at the back to allow manual rotation.  Also, the padded case also fits well with another idea of inserting a 1/4" machine bolt through the center axle and snug it down with a couple of large flat washers...when I say snugging it down I do not mean "tightening" but snugging it so the central bolt quadruples mag body integrity without creating internal binding.

For those wondering what the hell I'm talking about, as delivered the drum has a hollow central spindle with a 6mm hex drive.  The ONLY thing holding the case back on is four large and two small screws and while this is certainly sturdy enough for most, the first thing that jumped out at me was to run a bolt through the center...add a padded cordura, drum-shaped case and the drum will probably be able to withstand some pretty extreme shocks and bumps.

Internally the drum is very well designed and built and clearly reliable.

[SnakeWrangler]

Yes its after the mag is loaded. There are small plastic pieces that separate the bullets once they actually get to the rotary part of the mag. From what I have observed this is to keep the bullets from "binding" as they are moved in and out of the mag. If you take a hand full of bullets and line them up pushing the lead together the line will start to become concave or convex (depending on how you look at it). Those spacers seem to combat this problem, but at the same time they leave room for the bullets to rattle around.

I have not had any trouble out of the mag at all. The rattling simply irritates me a bit.

[Kilibreaux]

The spacing you see between loaded rounds is caused by the slotted "star" wheel inside the rear of the drum.  The rim of each round slips into these slots thus creating the separation you observe through the view slots.  The spacing is dictated by the need to cycle "layers" of shells down about two and a half turns, so the slot spacing becomes closer as each layer of shells moves inward.

A purely "peripheral feed" type drum would have each round separated by much less spacing, but the GSG drum is a REAL drum in that it uses both a slotted feed wheel to achieve rotation and inward/outward movement, combined with a slotted "housing" to move the shells in spiral fashion from outside to in, and vice-versa.  Where the GSG drum differs in that it uses a massive constant force "motor" spring that needs no winding after loading, and of course it loads single-round through the feed lips as opposed to an open back.

[Kilibreaux]

Today I completely disassembled the drum.  I planned to clean away all lubricant with the intent of using only dry lube after noticing the little "placeholder bullets" seemed reluctant to move smoothly.  Sure enough the strip of "bullets" and channel inside was heavily gritted.  I've already switched to dry lube for all other .22 uses since this does not attract and hold onto debris.

Unfortunately I observed a stress crack on the right side of the tower right where both the small screw that holds the back on goes, and the long screw that mounts the tower to the drum body.  Without doubt this area is going to fail completely at some point unless I repair it and look at reinforcing the outside.

The design of the drum is great.  The drum's operation is great, but the outer casing is of a rather fragile type of plastic, NOT what is used in the standard stick magazines.  The drum tower seems to be made of the stronger ABS material like the stick mags, but the body is shiny black plastic and due to the small "neck" area where the tower fits into the drum the plastic body is prone to fracture.

When I purchased the drum I did so knowing it was likely to be deficient in terms of construction, but aware that it would provide a good "pattern" for future development of a drum built to last.  I've got a lot of experience working with ABS and fabricating complex parts so it looks like I'll soon be delving into reproducing the drum housing from a much higher quality ABS material which will also be substantially thicker, and able to hold up to being tossed around.

For sure the 22 round stick mags have proven to be quite durable and reliable and for now that's the only mags to be relied upon for survival use.