Starting a STEN Mk V SBR in the US

[Vincent]

Attachment 52107

You don't want the ejector to be flush with the outside of the tube. The weld will be stronger if it is sitting down in the slot. Remember the magazine well will be sliding over this. So the weld needs to be in the slot. If you get any above the slot, you will have to grind it off so it's flush with the tube.. or the magazine well will not go on.

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[17thairborne]

You don't want the ejector to be flush with the outside of the tube. The weld will be stronger if it is sitting down in the slot. Remember the magazine well will be sliding over this. So the weld needs to be in the slot. If you get any above the slot, you will have to grind it off so it's flush with the tube.. or the magazine well will not go on.

Yea...that's why i ground off the old tube so it could sit down a bit lower and receive some molten metal on top, thus binding it to the tube. I would then file the excess off to match the outer contour of the tube. I suppose I should have left just a bit on to wedge it in there, yet provide room for the weld. I did not know about the mag interference issue...thanks for calling it out!

---------- Post added at 01:25 PM ---------- Previous post was at 01:23 PM ----------

17th,Fighting the springs to get the charging handle into the “J” slot was too much effort for this old man. So I did the conversion on selector to make it safe or fire instead of R & A. It’s very simple. You just cut a semicircle out of the tripping lever for the selector to pass through. Let me know if you want the detailed instructions.

I used some of the wife’s pottery clay to hold the ejector and a strip of beer can to shim it.

~V~

I like both of those ideas. I'll get some pottery clay and thin metal for the shim. I was thinking of the selector conversion to a safety. IO adds instructions in their plans which accompany the "guts". If you would be so kind as to post photos of the mod that would be of great help to me and others.

---------- Post added at 01:30 PM ---------- Previous post was at 01:25 PM ----------

Another option would be to just make another ejector, which would fit the slot in the casing, and interface correctly with the bolt.

That brings up another question:

By filing the ejector as I have, will there be strength issues with the part? It seems since I left the front profile alone and made my ramp down to the lower profile with a rounded bevel instead of a right angle, I should minimize the reduction in the strength of the part and not create a structual weakness. I mean....jeesh...we're only talking about knocking out an empty case that's held behing a spring extractor on one end. SHould not be much force impacting the ejector. Or am I a worry wart?

[17thairborne]

MODERATOR

Please delete two previous posts with wrong and duplicate photos. Moderator edit: 2 previous posts deleted as requested..

Sear aligns properly. Block aligns perfectly with the ejector during the loading, 'locking" and extraction phase. Is only when the block is rotated up and into the safety slot that the feeding groves foul with the ejector. That tells me the safety groove is milled too "high from the cycling grove. The problem with milling it at the proper angle is that the grooves would be too close together there would not be much metal from the tube between the two grooves. Too weak in my opinion. THis is why I conclude that milling the vertical grove more aft on the tube would solve this problem. You an see the thin line where I edited the image to show where I would mill the new upper grove. That will move the block aft enough to where it will not interfere with the ejector. You can also see if i milled the grove lower (closer to the long lower grove), there would not be enough metal between the two. Too thin I think.

[Vincent]

I will get a picture of the modified tripping lever and centering block up soon.

Don''t worry about you're ejector. You could file more away and it would is still be larger than the ones I have. They are shorter and still work fine.

[17thairborne]

Great....thanks

[Peter Laidler]

I don't really understand all the geometry that you are talking about except that there is a problem with the breech block fouling the ejector when the cocking handle is rotated uo and forwards into the safety slot. Is this correct? Bear in mind that I am not familiar with the single shot conversions too!

If this is the case, and it is a small amount of metal that fouls, then why not just leave the casing and ejector full size and unaltered - as it is - And simply machine away a small section from the front/side face of the breech block where it is fouling the ejector. The part that is fouling will be the radius of the outer forward edge and nothing to do with the important feed horns.

Or am I missing something in the telling here?

[17thairborne]

I don't really understand all the geometry that you are talking about except that there is a problem with the breech block fouling the ejector when the cocking handle is rotated uo and forwards into the safety slot. Is this correct? Bear in mind that I am not familiar with the single shot conversions too!

If this is the case, and it is a small amount of metal that fouls, then why not just leave the casing and ejector full size and unaltered - as it is - And simply machine away a small section from the front/side face of the breech block where it is fouling the ejector. The part that is fouling will be the radius of the outer forward edge and nothing to do with the important feed horns.

Or am I missing something in the telling here?

Peter,
It is such a large amount I was afraid it would alter the block in a very negative manner. That is why I elected to modify the ejector. I would have to take off a significant portion of the block where the feed horns are. In retrospect, the proper solution is to mill the safety grove farther aft of where the template renders it. On another note, if I use the selector switch with the below mentioned modifications, it will serve the same purpose as the upper bolt handle grove. It will, in essence, eliminate the need to use the upper grove. I could have just done nothing and not used the upper grove at all.

[17thairborne]

The welding is complete. A friend of mine referred me to a local welder who did an absolutely fantastic job. The welds on the tabs that connect the trigger housing to the tube look remarkably like the original spot welds done by ROT in 44. They have a slight recess and were done with the utmost of patience. He used a TIG welder and extremely thin wire, I think it was 1/32". He began with a tack, and then filled patiently until the level of the metal was just below the surface of the tab. For the welds on the trunnion and rear attachment ring, those were filled to slightly above the level of the tube. Very little filing was required. Here's the goods:

"J" at work:



Tabs welded to tube




On display in the bunker




More detail, but need to finish cleaning up these welds





http://castraponere.com/bloodontheta...N/Welded4b.JPG

[Brit plumber]

It sounds like the cocking handle slot is out of alignment with the mag port and ejection port by a few degrees. Does the sear align with the block OK (Or whatever it is with the semi conversion).

[Vincent]

Will the bolt still clear the bar in the center of the spring retainer if the safety slot is cut that far back?