MK3 STEN Photographic Profile

[Flying10uk]

Here are some pictures of my MK3 STEN (U.K. deactivated). This SMG differs considerably from it's older MK2 brother in the way in which it is constructed and is often referred to by some as a "throw away" gun. While I can quite understand why this may be stated perhaps some of the interesting and original design features are not fully understood. This would have been done in this way for ease/cost-reduction of production in time and materials.

Much thought must have gone into the design of this gun by the Engineering team at Lines Brothers for example the very simple yet brilliant idea of putting an external flange along the top edge of the receiver. This doesn't just serve the purposes of providing an easy to reach and convenient area to spot weld but also in doing this it also pulls the tube (receiver) in together tight along the join. The design of the trigger housing and guard, 2 pieces of metal, is also another well thought out design. The way in which it is bent up and includes an upper ring which slips over the receiver and strengthens the rear of the receiver. It also acts to retain the top of the stock mounting. When the trigger guard is welded in place this strengthens and completes the trigger housing assembly. The apertures in the receiver appear to have been punched out when the receiver was in the flat, as would be expected, thus saving valuable machine time.

Information

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[mrclark303]

Thanks for sharing, some interesting construction details among your pics there.

[Vincent]

Very nice pictures. Thank you for posting them.

It looks like a couple of the front busing rivets have been removed and the busing welded in. Is that part of the deactivation or a repair?

The hand guard is interesting too. I don’t remember seeing one like it before.

[Flying10uk]

They had to remove the barrel in order to cut a slot up most of it's length which isn't normally possible on a MK3 and so I guess the front bush was removed for this reason. The rivets were then replaced with weld to make it difficult to remove the barrel again and also simpler than using rivets for the firm doing the deactivation work. The long slot which was part of the U.K. deactivation process and permanently "killed" the barrel has now been replaced by a series of 5 or 6 holes because the European Union said so. There are some additional "viewing" holes in the underside of the receiver so that the slotted barrel can be seen if required.

The hand-guard over the ejection point appears professionally made and fitted with rivets. However. I have to ask why rivets and not spot welds were used to attach it to the receiver. The most obvious explanation is that it was done by some-one other than Lines Brothers.

[Lee Enfield]

...snip...
The hand-guard over the ejection point appears professionally made and fitted with rivets. However. I have to ask why rivets and not spot welds were used to attach it to the receiver. The most obvious explanation is that it was done by some-one other than Lines Brothers.

All MkIII Stens which I've seen have rivets holding the finger guard on, the easiest answer seems to be that they do double duty as part of the barrel support ring rivets.

[Peter Laidler]

Lee Enfield is correct. They are helical cut, one-way trip drive rivets

[Flying10uk]

Is it known if the ejection port guard is factory fitted at production or a post production mod.?

[Peter Laidler]

Standard factory fit for all Mk 3's. Your Mk3 doesn't have the all important UK safety mod but it does have the associated cocking handle. It doesn't have the modified rib either

[Vincent]

Your Mk3 doesn't have the all important UK safety mod but it does have the associated cocking handle. It doesn't have the modified rib either

Since it doesn’t have the hole in the body for the Mk5 Safety cocking handle, I would replace it with the original type.

[Brit plumber]

I don't think many people know that the first Mk3 gun butts used the cast abutment/locking plate from the Mk1 butts. If I remember I'll get some photos.