Group 42 Sells Out [Sten Gun]
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http://www.mycal.net/Group42/weapons/project/sten1.htm
By Wheats, Group42
At the beginning of World War II England suffered harshly from the German U-boat campaign. Supplies were in short supply. The British had just been pushed out of France and had to be evacuated from the northern shores at Dunkirk. Unfortunately, most of their military equipment was left behind. Great Britain and most of Europe were being forced into a battle for survival. Small arms of any type were extremely scarce, let alone weapons suitable for the defense of a nation. Enter the 9mm sub-machine gun. The entire Stengun family evolved from a basic design of simplicity. It was designed by Reginald V. Shepperd, directory of the Birmingham Small Arms Company, and Harold J. Turpin, the principal designer, in conjunction with the Royal Small Arms Company at Enfield. The name "Sten" was derived from the first letter of the last name of each of the designers and the first two letters from Enfield. The Stengun Mk I went from the design phase to production in less than three months. Several changes and improvements were made and the famous Mk II design was finalized. The entire family of Stens are noted for their outstanding performance and unrefined appearances. By the end of production, over 2,000,000 Stens had been made at less that $5.00 per copy.
Due to the simplicity of design large amounts of Stens were made by small job shops. Firms with no experience in firearms manufacture began production. Some firms were no more than one man with a vise and hand tools. This gives you some idea of the ease of manufacture the Sten presented. Hence the reason for this information.
WARNING!!! Actually constructing a working Sten gun will require the advanced permission of the B.A.T.F.! Constructing a Sten gun with advanced permission is a SEROIUS CRIME! Of all the many Sten guns that were constructed during the second world war, most of them ended up here in the United States. They were stripped of their receivers ( the part the B.A.T.F. considers the gun) and are now available from many sources as parts kits. These plans will focus on the construction of a new receiver that will work with these parts kits. It is very possible to put a fully functional Sten Mk II or Mk III together for much less than $200 Select a suitable lightwall steel tubing which is commercially available. For example, a fence post pipe (galvanized) is 38.5mm OD and 35.0mm ID, most suitable for use as a receiver. 4130 alloy steel tubing is the preferred tubing to use, referred to as DOM (drawn over mandrel), it is known for it's uniform size, wall thickness and smooth interior surface.
08/01/2013 20:55
Group 42 Sells Out [Sten Gun]
2 of 4
http://www.mycal.net/Group42/weapons/project/sten1.htm
Cut receiver tube to 12.65 inches in length. Then use the enclosed template by either gluing or taping over the blank tube. Make sure at least one end is flush with the tube. Recheck the alignment of the template with the blank tube. It is now a simple matter to remove all the shaded areas on the template. By using this method, layout time is reduced. This feature makes the Sten an ideal project for the handyman with a minimal amount of tools. The areas to be removed from the blank are as follows: 1. Recoil spring cap locking notches. These are the small “j” or “l” shaped cuts at what will soon be the rear of the receiver. 2. Bolt or cocking handle slot. This is the long slot that allows the bolt handle to reciprocate. This must be straight. 3. Sear notch opening. This is located on the bottom rear of your receiver. It allows the sear to hold the bolt in the open position. 4. Ejection port. This is the large opening on the right side near the front half of the tube. 5. Magazine port. Positioned on the left side opposite the ejection port, this opening is for the insertion of the magazine. 6. Magazine housing alignment slot. By allowing the magazine housing to rotate 90 degrees, this converts the magazine housing into a dust cover. This is located left, in front of the magazine housing itself. 7. Barrel sleeve latch hole. As the magazine rotates upward toward its’ shooting position, this prevents the housing from overtravel. 8. Ejector slot. The ejector in the parts kit will fit here. This is the slot at the rear of the magazine port. Be sure that the installed ejector does not interfere with the travel of the bolt.
Before making any cuts on the receiver tube, carefully read all of the instructions. The length of your Sten is not very critical. Most wartime copies vary in length to some degree. Do, however, make sure that the ends are square and true. The single most important cut of all is the cocking lever (or both handle slot) be careful to make it straight and square to the ends of your tube. To avoid problems, use the template. If you are using the template and for whatever reason things don't line up, now is the time to correct it, not after you have cut metal! Cut the sear hole last. Also, make sure that the slots for retaining the butt stock are 180 degrees apart. If milling machines and/or drill presses are not available, the entire job can be done with hand tools. After laying out the correct cuts and trying on all the parts that fit (without actually cutting), you may start. Simply drill a ¼ inch hole in each area to be cut out. By drilling more than one hole you can connect the holes using files and a hacksaw. It is best to leave these cutouts just a hair on the small side to allow for final fitting. Once cuts are made on the receiver blank, try the parts on the tube from time to time. This will help guide you along without mistakes. Once the parts are test-fitted and correct you can prepare the tube for welding. Welding can be done by any conventional method available. If conventional methods are not available, you can also use the brazing method. Brass rod can be used but it would be stronger using steel, even a coat hanger will do in place of a brazing rod. After final assembly and welding is completed, you are ready to hand operate the Sten and prepare to test fire. Make sure the sear will engage the bolt. If it does not, runaway gun will result. To test fire, use only one round at a time in the magazine. The Sten should fire the single round and lock the bolt reward in the open position. Check to see that the extractor pulled the empty cartridge case free from the barrel. Wear eye and ear protection during this stage.
08/01/2013 20:55
Group 42 Sells Out [Sten Gun]
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http://www.mycal.net/Group42/weapons/project/sten1.htm
Receiver Diagram. Trigger Group. Receiver Rear End Bushing and Main Spring Cap. Whole Gun Parts Layout.
Rate of fire: Weight: Barrel:
Length: Operation: Cartridge:
Feed: Sights: Recoil Spring:
Bolt:
1. 4. 7. 10. 13. 16. 19. 22. 25.
550 rounds per minute 6.62 pounds 7.75 inches long 6 groove Right hand twist 30 inches long Blowback, selective fire 9mm Parabellum Bullet weight: 116 grains Powder weight: 6 grains Muzzle velocity: 1400 ft./sec. 32 round detachable magazine Fixed rear, driftable front Wire diameter: .067 inches Spring OD: 1.00 inches Active coils: 15 Free length: 9.40 inches Initial length: 6.80 inches Final length: 3.20 inches Work stroke: 3.60 inches Weight: 1.327 pounds Cocking handle: 0.077 pounds Recoiling weight: 1.404 pounds Bolt max. dia.: 1.381 inches Bolt overall dia.: 5.75 inches Bolt body length: 4.21 inches
Barrel Recoil Spring Front Sight Magazine housing Sear spring Selector Spring Stock Trigger Ejector
2. 5. 8. 11. 14. 17. 20. 23.
Bolt assembly Recoil spring cup Barrel sleeve Sear Pin Selector Trigger housing magazine assembly Sear lever
3. 6. 9. 12. 15. 18. 21. 24.
Bolt handle Recoil spring cap Barrel bushing Sear Selector stop pin Trigger housing cover Trigger pin Trigger spring
Sarco 323 Union Street Stiriling, NJ 07980 (201) 647-3800 Parts kits
08/01/2013 20:55
Group 42 Sells Out [Sten Gun]
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http://www.mycal.net/Group42/weapons/project/sten1.htm
Ohio Ordinance Works Inc. P.O. Box 687 Chardon, Ohio 44024 (216) 285-3481 (216) 286-8571 (FAX) Parts kits and more
Global Sales, Ltd. 1091 Airport Road Minden, NV 89423-9030 (702) 782-4400 Parts kits
CATCo. 316 California Avenue #341N Reno, NV 89509 (707) 253-8338 Construction Videos
Tom Forrest, Inc. P.O. Box 326 Lakeside, CA 92040 (619) 561-5800 (619) 561-0227 (FAX) Sten Magazines
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08/01/2013 20:55