Aldis Brothers 1916 scope

Wonder if anyone has seen the Aldis scope on ebay item # 371005336218, I had one identical a good few years back, but they are not SMLE mounts they are from a sporter forget the year but was in contact with Holland & Holland at the time who give me the info.
The rear is very similar but the front mount is a straight leg compared to the SMLE mount which comes off at 90 degree's.

Could be wrong regarding the above but sure some of the Sniper collectors will chime in.

British WW1 Aldis Brothers 1916 Snipers Telescopic Sight Holland Holland Smle | eBay

Large quantities of parts were sold off in the trade after the war put-together scopes were still being sold into the '50s. (P-H catalogues of the era)

The mounts on that scope are actually modified original Purdey rings.

Went for £820 in the end, seems the original description had been changed at some point.....

---------- Post added at 09:25 PM ---------- Previous post was at 09:18 PM ----------

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Originally Posted by Simon

The mounts on that scope are actually modified original Purdey rings.

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Simon how modified ? is both or just the front one. I,ll try and dig out my pics of the one I had, it was excellent condition and come with the case.

The rear mount has been shortened and re-shaped and the front mount has been rotated through 90 degrees and the end re-shaped.

Haven't got any pictures to hand of an un mullered Purdey but I'll post some tomorrow.

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Originally Posted by Simon

The mounts on that scope are actually modified original Purdey rings.

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Yes, and the funny thing is that H&H, unlike Purdey, understood that the forces of recoil throw the scope forward before they throw it backwards and designed their rings accordingly. Yet when they went to adapt these Purdey rings they perpetuated Purdey's error by having the 'hooks' facing rearwards. Odd.

I'm not sure that I'd wholly agree with that statement Rob. I think the first sentence is based on fuzzy logic ............ When the rifle recoils the rifle and the sum of the parts recoil in unison as they are effectively one mass. The add-ons don't tend to throw or rock forwards at the moment of recoil, they actually attempt to remain in the same lateral plane due to....., anyway...... In much the same way as the cup or book on a table cloth does as you whip the cloth away. But with our telescope, because it is solidly fixed to the rifle, it acts as part of the mass in much the same way as the, say, foresight block band or the protectors or the handguards - or the magazine! They are not independent or neutral masses while they are held firmly

In this regard, it doesn't matter which way the claws face. What DOES matter in the physical sense is that the bracketry is solidly fixed. A good example of something similar not being fixed is a commercial mount where we have all seen the telescope slide in the tube or the dovetail clamp slide on the rail. But that is something else entirely.

It is in this solid mass state that the whole recoils and sets about its 'line of least resistance' rotary moments. Therre's a bit more to all this physics rubbish of course but.............

The best rifle / scope combo to clearly demonstrate Peters cup on a table cloth analogy is perhaps the Winchester A5 / S.M.L.E or indeed the Springfield / Unertl arrangement. You'll hear people talking about how "after each shot you have to pull the scope back into battery as it moves forward because of the recoil". What is happening in reality is that when the trigger is pulled and the rifle recoils the scope effectively stays stationary and the rifle recoils under it giving the appearance that the scope has moved forward.

Purdey pics as promised too.Attachment 50584Attachment 50583

Cheers,

Simon.

Yes, I see your point about the phrase, "thrown forward" Peter; poor choice of words perhaps. I took it as a given that we all understand and can visualize 'in slow motion' as it were, the forces and motions involved, if not the proper engineering terminology! ;)

It would be interesting to see in slow motion a high speed film of a SMLE with a Purdey/Aldis firing. The rear 'leg' does almost nothing while the front 'leg' attempts at a 90° angle and a distance of a couple of inches from its point of attachment to transfer the backwards acceleration of the rifle to that 2lb scope!

When the scope catches up with the rifle and the rifle decelerates into the firer's shoulder, then that rear hook does come into play, but it seems to a mere layman like me that those forces are only a fraction of the initial acceleration.

What I was actually emphasising Rob was not the mechanics/slipping of the thing but more the fact that whether the hooks are forward or rear facing has no effect on the robustness of the mount

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Originally Posted by Peter Laidler

What I was actually emphasising Rob was not the mechanics/slipping of the thing but more the fact that whether the hooks are forward or rear facing has no effect on the robustness of the mount

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Not sure I follow there Peter. When I think of "robustness" I think of the extent to which the mounts are 'linear', rigid, close fitting, and transfer the forces between the rifle and scope without developing play over time, while equalizing as far as possible the load between front and rear rings/bases.

The offset front point of attachment also seems inherently unsound to my eye: the forces are multiplied by the leverage created by the offset of the front base. The front ring must have taken almost all the load at that point. Something else H&H avoided.

The designer of that 'hook and peg' system obviously believed that the bulk of the forces would be transferred through the rear ring and base it seems to me. The hook as made, does almost nothing to control the initial movement as it is open on the wrong side.

A nice video clip that demonstrates the forces acting upon a scope and mount under recoil, yes I know its a .50 but the Physics is the same.

high-speed video of scope and barrel flexing on a 50BMG - YouTube

Pretty shocking how even a setup like that flexes! Seems David Lloyd was onto something with his massive scope mounts!

https://www.milsurps.com/images/impo...4097331r-1.jpg

Another vid here; watch to the end.

http://www.youtube.com/watch?v=08TMXzDrv00

Optical illusion caused by the optical abberration the curvature of the lenses imparts upon the image as it reaches the edge of the compound curvatures (thickness and roundness). The eye is not quick enough to absorb the changes. Look through a telescope at the far edges of the lenses to see what I mean. That's why your eye should concentrate through the centre 1/3rd