SMLE sight usage

[Grayrock]

Can anyone describe how this sight is supposed to work? I can push the left side and slide it, but is the right side supposed to twist for smaller adjustment? If so, it doesn't want to do that.

 

[BreechFace]

The "wormwheel" on the right should allow for small gradual movements as opposed to the gross movements one gets with sliding the elevator with ones pinched fingers. The right side of the sight has corresponding threads that match the wormwheel to get fine adjustments.

You are saying the wormwheel doesn't move? If not, you may need to use some kroil or some other penetrant and try and free it up.

 

[JohnB-40]

BreechFace is spot-on,try a small amount of penetrating oil to free it up. Sometimes the indented track on the sight body itself is messed up causing it to jam . You will have to workout where the POI of the rifle is depending on what cartridge you use. The SMLE sights were calibrated for the MK 7 .303 round with a bayonet fixed.

 

[Grayrock]

The worm wheel spins freely if I release pressure on it by pressing from the left. When it's in contact with the threads it's very difficult to turn without abrading my fingertips. I'm not sure if the threads are messed up or what. The threads don't appear to be messed up. John B-40: do you mean the presence or absence of a bayonet is going to affect the accuracy? Is that due to barrel harmonics or is the bayonet putting stress on the barrel somewhere?

 

[BreechFace]

Do you hear anything resembling a 'click' when operating the wormwheel? I believe each 'click' represents a fine adjustment of 5 or 10 yards.

Your picture of the threads seem like they are in working order. It has to be something not meshing correctly with the wormwheel and the threaded side of the elevator.

 

[JohnB-40]

John B-40: do you mean the presence or absence of a bayonet is going to affect the accuracy

I don't know if the term accuracy was affected is the correct wording or not. I believe it was do with the distance of point of impact of the projectile in relation to the sight setting. If you fire 10 rounds,you could have a good groupings,just higher or lower on the target. What caused this could be harmonics,they do have a forend stud and spring to give upward pressure on the barrel. All Enfields were sighted this way because when the Brit army (especially in the Great War) was ordered to "stand to arms",preceding that the order "fix bayonets" was issued. The Brit's excelled at volley fire,where the officer or NCO would shout the range and a couple of hundred Enfields would bang off and hit the "beaten zone" with deadly results as a trained soldier could fire 15-20 aimed rounds in 1 minute. The German's thought they were facing multiple machine guns.

 

[Mk VII]

You push in the catch on the left slightly and use your thumb nail to move the notch up or down. You should be able to do it in the dark.

 

[792mauser]

^
Yup. Push in slightly on the button and it becomes possible to move the rear sight in small amount as needed.

 

[shoobe01]

The wheel on the right is one of those small parts that does not like the various storage greases or the wartime paints that got applied. Once working right it really works right, easy to turn as a fine range adjuster. But it might take removal and soaking for a while to get it to work.

I've had a couple so broken I was 100% positive they had a metal issue, threads are broken. First cleaned them and... they worked fine then.

 

[Grayrock]

The wheel on the right is one of those small parts that does not like the various storage greases or the wartime paints that got applied. Once working right it really works right, easy to turn as a fine range adjuster. But it might take removal and soaking for a while to get it to work.

I've had a couple so broken I was 100% positive they had a metal issue, threads are broken. First cleaned them and... they worked fine then.

Is there a video or tutorial on how to disassemble and clean one?

 

[shoobe01]

In case I wasn't clear: I have never risked trying to disassemble this small fussy looking thing, and the whole sight assembly is pinned and brazed on; people change them out but I haven't done that.

When I cleaned those I mentioned, I just soaked them for a week or so. Not immersed, as it's on the gun, but rags under it and around some bits, drip cleaning fluids and then oil on it every time I walk by, periodically scrub with toothbrush to remove gunk, carefully (for cleanliness, your eyes and clothes) blow it out with shop air, and so on.

 

[BreechFace]

Try some Kroil on it if you have some, that stuff works great. As @shoobe01 said just work on it on the rifle, it should free up with some soaking, brushing and compressed air.

 

[CapnMac]

do you mean the presence or absence of a bayonet is going to affect the accuracy? Is that due to barrel harmonics or is the bayonet putting stress on the barrel somewhere?

He's actually referring to the government specification for how the sight is calibrated.
SMLE barrel--if memory serves--is "fitted" (UK term-of-art is "fettled") with stock contact at three points, receiver, mid-barrel, and stock cap.
With the bayonet fixed, the end cap bears down more than without.
Change of POI is enough to table (it's online somewhere) but well withing the 3-4 MOA acceptance standard the UK used. I want to remember--and may well be wrong--the change withe/without bayonet is around 1/2 to 3/4 MOA.

 

[Grayrock]

I'm soaking it in mineral spirits right now. Will check it out in about 20 hours. Brush it down, blow it out and apply some Rem-oil. Hopefully that will rejuvenate it.