Tanio Koba GM7 (Colt 1911), HW

History
Yup, this is a modelgun of the well-known Colt 1911, a hundred years old pistol.

For more information about the real firearm please see the usual internet resources - there's too little space on margin to put it here


Modelgun
Tanio Koba is a legendary designer of modelguns and airsoft pistols. He worked in the industry from the very beginning, starting at MGC. Many solutions that are now taken for granted have been designed by him somewhere along the path. After MGC was closed he opened his own company that designed airsoft parts and models, and finally released a modelgun based on Colt 1911.

This model was named GM-7, as it follows the latest GM-6 model of Colt 1911 designed for MGC in 1983.

GM-7 models are manufactured in small batches of a few hundred pieces (200-400 from what I've read). There are several variants: PC Carry-SF, Rev.1 SFA, CUSTOM Rev.2 SW Model 1911 Type A/B/C, GM-7-2nd Tactical Basic and GM-7-2nd MEU
http://www.taniokoba.co.jp/gm7_2nd01.html
http://www.taniokoba.co.jp/gm7sw1911cust_rev2/gm7sw1911custom.html
http://www.taniokoba.co.jp/MEU/gm7_meu.html

At least one company, BWC (Bluing Works Company), customizes these models and releases them in small batches of 20..50 pieces:
http://www.bwc-bluingworks.com/Product/complete/CUSTOM_COVERT/CUSTOM_COVERT.html
http://www.bwc-bluingworks.com/Product/complete/TACTICAL_CUSTOM/TACTICAL_CUSTOM.html
http://www.bwc-bluingworks.com/Product/complete/LAPD/LAPD.html
http://www.bwc-bluingworks.com/Product/complete/metal_SIS/metal_SIS.html
http://www.bwc-bluingworks.com/Product/complete/3.8_ultra/3.8_ultra.html
BWC also manufactures "Metal Cartridge Chassis Set" consisting of a replacement metal skeleton (goes inside frame), a steel ejector and metal cartridges:
http://www.bwc-bluingworks.com/Product/custom-parts/chassis_set/chassis_set.html

You can find another Tanio Koba GM-7 review by claymore here:
https://mp40modelguns.forumotion.net/t1440-tanio-koba-gm7
And a discussion of the system:
https://mp40modelguns.forumotion.net/t2326-tanio-koba-gm7-colt-1911-comments


I was fascinated by the fact that Tanio Koba designed an improved version of a Colt 1911 modelgun. When my MGC 1911 broke, I used it as an excuse to get a TK GM-7 ;-) I did not choose a specific model, I just wanted to have TK mechanism in it.


Box
Tanio Koba delivers his models in a plain light-brown cardboard box. It is adorned with several white stickers. Side carries "STGA PLUSTIC MODELGUN GM-7", "PATENT APPLICATIONS", "OPEN-DETONATOR BLOWBACK SYSTEM", "DESINE & PRODUSE BY TANIO-KOBA JAPAN". The top has an STGA label that certifies it is a safe plastic toy, a large label repeating text from the side in a different layout, and the most important sticker in a corner - it names the variant and price. In my case it is "PC CARRY-SF TACTICAL BLACK MOD:PC1-350" priced at Y36750. "SF" stands for "Springfield" I guess.



After lifting the box flap open there is a blue leaflet with general information printed at the first page: patented blowback system, a brief MGC modelgun history and data. Inside the leaflet there is a parts diagram, a price list and operating instructions.








Sheet 2 added by Cerwyn Sept 9th 2011











Inside the box you should find a modelgun with a magazine, as well as tools: transparent plastic loading tool, small hex screwdriver and a wire tool of unknown function. Cartridges are not supplied - you need to order them separately. They are cheap and readily available though, so not a major problem, just something to remember about when ordering.




Modelgun
It is a solid model of Colt 1911, heavy, with good finish.

(note: surface is covered in dust very visible in sunlight. In reality it looks better than photos.)



Frame and slide are made of HW material of dark grey colour. This contrasts with black metal details (sights, manipulators), black plastic grips and a metal silver hammer.

Slide is marked "MODEL 1911-A1 CAL.45" on the left side, "SPRINGFIELD ARMORY" on the right, with a Springfield logo in front of the text (opposite of MEU variant). Slide has cocking serrations at the back.




Sights are simple dovetailed metal ones, like in MEU, but painted with white dots, and the rear one is secured using a large, normal screw.



Frame has several markings: "SPRINGFIELD GENESEO IL USA" and "JAN.09/STGA" on the right side, and a single "T" in a triangle near the front of the trigger guard, on the left side. All markings are clearly defined and readable, a huge improvement from what I see on my MGC 1911.



Grips are checquered and plastic, held by two screws.

Barrel is made of HW material, but chamber area that is seen through the ejection port is covered with a metal plate marked "45ACP". This plate gets scratched during normal operations of the model. Barrel itself is black and it has a usual horizontal metal tab inside. Under the barrel you can see a silver return spring rod. It is a full-length one, so it will stick out the front when the slide moves backwards.



Trigger pull can be adjusted - there is a small hex screw that can be reached with an L-shaped hex screwdriver.


Magazine
Magazine supplied with this model is made of metal covered in black finish. The follower is metal, and black too. Bottom of the magazine has a small bumper with a "meat tenderiser" surface.



Finish gets worn off quite easily, it also attracts cap residue. Mine is already reddish near the top. Good news is that MGC magazines fit this one - verified with a stainless steel magazine from my MGC Colt 1911 MEU. Stainless steel finish is much more resistant to cap residue!

Capacity: 7 cartridges, how else in a single-stack?


Cartridges
Tanio made a small revolution (or return to the origins!) by using plastic cartridges. They are very cheap, available in large quantities: 20 or 60 per bag. Cartridges are an open BLK design, they consist of just two parts: a cartridge and a metal insert to plug the bottom.




Material used in cartridges is slick, helping with loading them in the chamber and ejecting. Smooth surface also helps to work with the rubber o-ring at the detonator pin to operate without too much friction.

In the past MGC produced plastic .45 cartridges, I suspect that TK returned to this idea to lower production costs and make the design simpler, especially as he is not a mass-manufacturer.

Except for insignificant scratches on the outer wall, and black marks (rubber and cap residue) inside, these cartridges seem quite durable. As they are very light, they are ejected much further (with more force) than in MGC 1911 and at the same time they cause less damage.

Cartridges use a single 7mm cap loaded with the charge facing up/front.


Firing
Load cartridges with caps, magazine with cartridges and model with magazine.
Rack the slide to introduce the first cartridge in the chamber.
Make sure safety is off, hold grip to disable grip safety, pull the trigger when ready.

This model goes off with a very satisfying BANG!
On par with MGC 1911, if not even stronger - indoors your ears might ring a bit.

Repeat until you run out of cartridges, slide should lock back.

Cartridges seem to fly a long way, being so light, and they tend to hide much better than their heavier counterparts in other modelguns. So far I've lost just two, and I don't worry about it!

Remember to clean the model and the cartridges after your firing session. Plastic cartridges can be cleaned more easily than other types, as they have a very simple design. Barrel should be rinsed with water, detonator pin removed and cleaned thoroughly every 50-70 shots. O-ring rubber will use up, just replace it with new one if the damage prevents correct operation. New o-rings can be ordered from TK in sets of 5 per bag (each o-ring comes together with a retaining c-clip and a washer).



I bought my GM-7 second-hand and I do not know what was its mileage, but the rubber lasted for over 50 shots. It finally blew off. You can easily notice it - cap still goes off, but there is no blowback. You shouldn't continue firing, as the rubber can jam somewhere.


Problems
No major problems with this modelgun so far :-)

A minor problem is that as it uses open cartridges, cap charge might fall out of the cap. This might result in a dud (hammer falls without a bang), a feeding problem (charge gets stuck inside the model) or a premature detonation (charge mangled in detonator pin). So far I've had a few duds - due to cap quality issues. Similar happens in other designs, except that charge is left inside the cartridge and not somewhere inside the model.


Basic disassembly
Disassembly is similar to my MGC Colt 1911 MEU, with one MAJOR difference: return spring guide rod is full-length, making it much more difficult for me to take it out. I still have not figured out how to do it safely and easily, so far almost every time it flies out when my fingers slip off the spring.

(see Instruction Sheet 2 added above. Push the Guide Rod through the bush compressing the spring. Place the Hex. Wrench / Allen Key provided through the Guide Rod's drilled hole. This locks the rod and spring in compression making removal easy. Reassembly is much easier also as the Guide Rod can be controlled by your thumb as the Allen Key is removed)

In real Colt 1911 spring is held by a spring plug, which is held by a bushing, so they can all be removed while slide is still on the gun, through the front. In MGC and TK models the spring plug has a collar that prevents it from sliding out the front.








After separating the slide from the frame you will notice that a lot of elements are different than in a real Colt 1911 or a MGC 1911 modelgun:
- barrel has an extra spring wrapped around its outside. This is designed to reduce stress on barrel and avoid breakage (see MGC 1911 information elsewhere in the forum).
- barrel does not have a cartridge ramp - it has been moved to the frame.
- breech block is much different. It is held in place by a tri-wing screw, and seems to be made of two parts - the front is black plastic, the back is metal. MGC has a single-piece metal one, with a metal tab to block it in slide.
- return spring guide is full-length, and it sticks out the front during slide/barrel travel. Compared with MGC it has an additional rubber buffer, as well as a separate piston with its own spring, mounted near chamber end. This should reduce stress on barrel and make operation smoother.
- detonator pin almost sticks out of the chamber, as it has to reach deep inside open cartridge. In MGC model detonator pin is not so visible, you have to peek inside the barrel.
- unlike a real 1911 the barrel has an extra spring around it. Don't forget to put it back in correct orientation when assembling.
- metal guide rails on the frame are full length, while in MGC they had a plastic section in front of metal - it could snap when stressed. Also a hole for the slide stop is now within the metal bracket inside the frame, not just plastic frame.
- disconnector is near the right side, while in MGC (and real 1911) it is right in the middle.

Other than that - mechanism in the frame (sear etc) is different (simpler) from a real Colt 1911, or MGC modelgun. Tanio Koba based it on Tokyo Marui airsoft model, most likely to simplify production. This is of course not an issue for firing, disassembly or cleaning.


Overall
This model can be highly recommended!
It works good, it looks good (better than MGC), it is designed by the legendary Tanio Koba. The only low points are the high price and probably a difficulty obtaining spare parts.
Apart from the financial aspect decision seems quite simple