Building the Canadian Semi-Auto STEN

Well it seems that I couldn't resist and went on with making another cut on my tube BEFORE I have a bolt conversion kit. Though I promised myself not to, I did it anyway. It is my little participation on the subject.

https://www.milsurps.com/images/impo...t2008005-1.jpg

https://www.milsurps.com/images/impo...t2008006-1.jpg

Don't laugh at my slippers please. :rofl:
https://www.milsurps.com/images/impo...t2008007-1.jpg

https://www.milsurps.com/images/impo...t2008008-1.jpg

Woups! One more broken drill bit! That makes 3. Next time I buy some, it won't be just plated Titanium. Better put some more dough on it and get some tools that last.
https://www.milsurps.com/images/impo...t2008009-1.jpg

Santa Claus has his helpers, I have my son to whom I say thanks! :super:
https://www.milsurps.com/images/impo...t2008010-1.jpg

By the way, Anthonin did not really use my tools but it made him feel "grown-up" posing for the picture. ;)
https://www.milsurps.com/images/impo...t2008012-1.jpg

I went to the second next drill bit ( in 1/64th increments) to widen the holes but I should have skipped 2 at a time. Result: the drill bit bit and broke.
https://www.milsurps.com/images/impo...t2008013-1.jpg

https://www.milsurps.com/images/impo...t2008014-1.jpg

https://www.milsurps.com/images/impo...t2008015-1.jpg

Even "Capitain Haddhock" from Tintin gave a hand! :lol:
https://www.milsurps.com/images/impo...t2008016-1.jpg

Here is a proud boy and a good photographer
https://www.milsurps.com/images/impo...t2008017-1.jpg

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Update! :)

This morning the gun got parkerized. It looks nice except that some of the OA welds wouldn't park - guess I should have used a different rod? It's just a cosmetic thing tough. On the whole it looks pretty good.

Had the now registered completed Sten out to the range today to make holes in paper & test function.

It was a partial success. Brewster was there with me and shot some video of the event, so hopefully that will be up soon.

The gun does go Bang and is definitely a firearm. It also shoots to point of aim at 25 yards.

Bad news is I only got to run about 10 rounds trough her, pretty much as a single-shot. The issue is that the SAS3 bolt geometry is all wrong inside the extractor cut, so the extractor is not camming over the casing rims. For each shot, I had to manually depress the back of the extractor and shove the bolt forward so that I could get the pin to hit the primers.

I had two extractors available. On one I filed the bevel to a more gentle angle, but tht was not enough to solve the issue.

I took a closer look tonight and think I have solved the problem. Got some metal stock and made a small shim. I epoxied the shim into the extractor cutout in the bolt body so that the extractor now sits up higher at the proper angle, and also the back of the extractor is no longer fouling on the tube body when cocking. Hopefully I can get out again next week to give her another go. It is feeding drill rounds now though - that's a good sign IMHO.

Since I saw the STEN thread on CGN, and recently have been in the liking of milsurps, i decided to check out this forum, and well, here i am in the sten thread.

So, i've been looking googling for blueprints on google for about half an hour, visiting different websites, etc. When i stumbled upon this:

http://infinitearms.com/images2/d/17...BLUEPRINTS.pdf

I dont know if its very accurate, but its sure as hell is a nice guide.

Alex.

PS. cant wait to hear more about this project. I feel like making one myself, or maybe I could try to be different and build a Bren instead.

ok, here are the much-anticipated (yeah, right...) videos of yesterday's testing of the Sten.

Video one started out with so much promise, only to end in disapointment. This is when we discovered the extractor wasn't snapping over the rim:




Next, we had our first sucess. By manually pressing the extractor over the rim and shoving the bolt forward, we got the first round to fire:




And in this final video, we checked to se if we could do a string. Alas we couldn't. Again, the extractor was the issue. Interestingly though, a sten does not need an extractor as it's a blowback design with fixed ejector. If I had brought a set of punches with me, we could have removd it and been in business. Ah well.





In the end, we fired around 10 rounds between Brewster and I. Next weekend I hope to shoot some strings, IF my extractor fix worked and IF no other build quirks pop up to defeat me!

Well guys, today was mock-up day! Good thing I did, I found that I overfiled the cuts on the tube where the end cap goes. I'll have to make a copper sleeve and rebuild the gap with the family MIG.

At least, things are coming together slowly but surely. Next tube I do I'll have it milled out. The lack or kraftmanship showes a little too much on this one. Looks like it was made in Afghanistan ! :lol:

Click to view the original image

Click to view the original image

Click to view the original image

Click to view the original image

Click to view the original image

Click to view the original image

Click to view the original image

Click to view the original image

Well,

I'm now in posession of a registration cert for mine!

WOOHOO!

I've tested a couple of primed cases, and need to shorten my firing pin a bit. No big deal, just a bit.

I installed the front sight tonight, which was interesting 'cause I only hade one triangle needle file handy, so it took a while to do.

I also cleaned up those ugly welds a bit. Not perfect, but much nicer anyhow.

So, I'm now, effectively, complete. I need to bring the gun down to the CFO this week to get it verified, but it's now done.

Woohoo!!!!!!

NS

Allright, here's a short vid of it running as a repeater. It was still hanging up on feeding periodically, but maybe only 20% of the time. I now know this is because I had the cone angle wrong at the chamber end of the barrel . It was too shallow. (I measured two original barrels and used that average angle to re-cut my barrel bevel) I put it back in the lathe and re-belled it a little steeper and it now feed dummy rounds much more reliably.

I have anothe build in progress, figured on filling in some "blanks" in the production process :)

Here is the steady rest being used to counter-bore the tube for the barrel collar:
https://www.milsurps.com/images/impo...P9092638-1.jpg
Mocked up to ensure fit:
https://www.milsurps.com/images/impo...P9092639-1.jpg
Scribing the lines on the tube (I find this works better than using the template). You need a scribe and a surface plate:
https://www.milsurps.com/images/impo...P9112643-1.jpg
Cutting the templates out in the mill:
https://www.milsurps.com/images/impo...P9172645-1.jpg

Here is a pic of my SA Sten.https://www.milsurps.com/images/impo...HPIM0411-1.jpg

Here are some pics of the one I finished (after parkerizing):
https://www.milsurps.com/images/impo...PA092685-1.jpg
https://www.milsurps.com/images/impo...PA092683-1.jpg
And next to a real brit MkII sten:
https://www.milsurps.com/images/impo...PA092682-1.jpg