Sten MK2 stock falling off while shooting
Posted 14 October 2020 - 12:36 AM
Ive tried replacing the recoil spring with 2 others and also swapped recoil spring housings with one from a known good Sten MK5. Ive also tried replacing the bolt with a steel bolt instead of the brass one. Nothing seems to be binding, Im at a loss as far as what is going on.
Posted 14 October 2020 - 01:52 PM
I had the day off today and decided to tinker with it. The button on the return housing was super easy to push in and my stock was a little loose. I took a piece of paper and folded it to the thickness of the a lot that accepts the stock and removed layer by layer until the stock would just barely snap into place. The stock still is loose on the bottom but has no vertical play anymore. Now the button is just a little sticky when pressing it in. Ill have to measure the round portion on a few Sten stocks to find one with a larger diameter. Ill add photos below
Posted 14 October 2020 - 01:58 PM
Edited by Homealone1, 14 October 2020 - 01:59 PM.
Posted 14 October 2020 - 05:42 PM
My MK II loop stock was too tight, and I had to use a rubber mallet and tap it off. I bought a MK V (wooden) stock, and it fits perfectly. I understand there is a lot of variance in specs, For example, have to try different magazines to get some that fit the magazine well. Perhaps try a different stock.
Posted 14 October 2020 - 06:17 PM
Posted 14 October 2020 - 06:33 PM
Shooting Germans and your gun falls apart!
Posted 14 October 2020 - 06:46 PM
Howd you like to be in ww2 and be issued that sten
Shooting Germans and your gun falls apart!
I’d just be happy it reliably feed and ejects lol
Posted 15 October 2020 - 12:58 PM
It failed with Heydrich,,,
Because the resistance fighter tried to fire the STEN with the stock removed.
The spring cap came out of the tube with the first shot and the gun was useless after that.
A mistake that cost them their lives.
Posted 16 October 2020 - 07:08 AM
Is the spring attached to the cap? Is the cap rotated into the locking position? Are tabs broken off the cap? The gun can be fired without the stock, I just don't know what you'd hang on to though?
The Sten guns function very well or the Germans wouldn't have bothered making them. Of course on the other hand the British Sten is a copy of earlier German guns that all functioned very well.
Posted 16 October 2020 - 09:52 AM
On mine the spring is very tight in the "spring return housing", the "spring return cap" presses in and turns easily.
Removing the stock seems simple enough, not a lot of pressure to push the "spring return housing" back thru the locating hole in the stock.
The British Para's actually had a blanking plate to fit into the back of the STEN so it could be fired with the stock dismounted.
It is carrier in the in a compartment on the Airborne bayonet frog.
Posted 18 October 2020 - 12:43 PM
Richard, that is a cool piece! Designed for the MK5 though.....since you have two grips to hold onto. I recalled seeing it in Seagul's book when you posted the picture and had forgotten about it. I'm guessing finding one of those will be a project?
To the OP, swapping out to a MK5 setup may be risky. Bolts are different and old springs may have additional compression due to the shorter stroke/ distance. Best to swap out working MKII parts.
Posted 18 October 2020 - 06:07 PM
I have a Mark II Sten that was bought back from Korea and registered during the 1968 Amnesty. It sat in an attic for many years. I do not know if it was ever shot in this country. I bought it about 1984. It is pretty beat up. It came with a T-stock. I needed some parts and purchased a parts kit. I think from Sarco. The parts kit came with a loop stock. I have fired the gun with both stocks. The loop stock always falls off, some times in the middle of a burst. I have never had that happen with the T-stock. The dimension from the center hole of the loop stock is noticeably longer than the T-stock. I have looked at other Stens with both kinds of stocks. I think there is a variation in the size of the part of the stock that attaches to the gun, depending on where and when the stock was made. I think that it is more noticeable with the loop stocks than the T-stocks. I think you should check the dimension on your stock and then see if you can find someone selling stocks and get them to measure a few for you.
Posted 19 October 2020 - 08:27 AM
If spring has lost strength then I could see lack of pressure on end cap could let it move forward allowing the stock to move down and possibly off
See how much resistance is on the cap when you push it by hand
Edited by Barry, 19 October 2020 - 08:30 AM.
Posted 20 October 2020 - 09:41 PM
My Sten is having the same problem with the stock sliding off. It seems that the recoil allows the cap to go in just enough to release the stock.
Note that my stock is not original to the Sten. The original owner lost it somehow. I'm definitely open to replacing it, but would prefer the loop type. Meanwhile, I'll give Homealone1's fix a try.
Posted 22 October 2020 - 08:10 AM
If you don't have a range timer to verify it, go online and note the cycle rates of other Stens being fired. If yours is noticeably slower, then it would be additional evidence that your recoil spring (return spring) is damaged/too weak/too short.
Posted 22 October 2020 - 04:12 PM
I already replaced my recoil spring with a new one. It might have helped some, but didn't solve the problem.
Posted 22 October 2020 - 08:02 PM
Bad springs, the plunger/cap should never move forward. RTG has NEW springs in stock. I mean new, not surplus used, but new to you. Take your spring out and measure it. It should be at least 9.5" at the least. The rear cap lugs have to be in the slot and rotated to the locked position. HTH
Posted 22 October 2020 - 09:56 PM
My new recoil spring measures right at 9". I bought it from Northridge and it definitely appeared new. I just ordered the spring set from RTG Parts and will let y'all know if it solves the problem.
Posted 22 October 2020 - 09:58 PM
I have to push hard to get my cup into the tube. Its so tight I have to use a pliers to twist it out