This optical sighting system was designed by Parker-Hale for fitment to practically any sporting rifle of the day.
Advertised from the early 1920s until shortly before the Second World War,
it provided an economical means to improve the sighting of small game with rimfire small-bore rifles.
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The 2X magnification objective lens could be clamped to the front of the barrel
of any rifle that had no other obstructing foresight in place.
A rear-sight clearing or correcting lens could be fitted in place of most of the contemporary rear aperture eyepieces.
At a time when an imported basic Winchester telescopic sight cost about £8 with its mounts,
the "Universal" set cost little more than £1 with your chosen lens type.
The system was effectively a then latter-day evolution of the early "Lattey" design of Galilean sight that
provided First World War snipers with an improved sight-picture over their Short Magazine Lee-Enfield (S.M.L.E.) rifles.
The 1925 A.G. Parker advertisement for the Universal Optical Sight Set is shown below.
As can be seen, the sight system also accommodated target shooters,
but one needs to be reminded that such an optical sight set-up would not have been eligible for most target shooting at that time.
The only competitions in which it could have been employed would have placed it in competition
with such as the aforementioned Winchester, or the similar contemporary the Stephens No 368 telescopic sight,
each respectively with 5 and 6 times magnification, leaving the Parker-Hale "Universal" sights completely outclassed.
Parker-Hale had also, in 1933, introduced their own telescopic sight, the P-H "Targetscope", modelled on the American Fecker product.
Marketed both by A.G. Parker and Parker-Hale, the Universal Optics were realistically only for use in the field.
Ten years after the above advertisement, in 1935, the Universal sight was relaunched in an "improved" version;
but as conflict loomed in Europe in the ensuing years, production shifted to more important weapon ancillaries,
and the Universal wa not reintroduced post-war.
The last posting for the product in the 1938 catalogue also gave a hint that purchasers of the sight
had been experienceing difficultie in accuracy probably related to incorrect fitmen to their rifle.
In bold lettering, prominently centred in the page, was the text
' We cannot point out too clearly that an Optical Sight cannot be "stuck on",
it must not be capable of sideways movement, and must therefore be "fitted".
The lens must be just right, and must therefore be "selected".
If you want a satisfactory job we must rely on your co-operation
after carefully reading these remarks, unless you prefer to send us your rifle.
This was an effective admission, apparently not mentioned prior to 1935,
that the sights could not easily be added to the rifle and removed on a frequent or "as needed" basis.
In fact they were both less versatile and effective than a properly mounted 'scope,
which could be removed and re-fitted at will without altering the rifle's zero.
Additionally, the choice of lens was critical.
The Universal Optical system, at first glance, appeared to offer a cheap
and practical alternative to a telescopic sight, but the truth was somewhat different;
leading to most of them languishing unused and undiscovered for many years in their dust-covered boxes.
See also the Parker-Hale CMT rifles , the Parker-Hale_Dewar_rifles
and ParkerRifling, A.G._and_A.J. Parker_and_ Parker-Hale, Parker-Hale Targetscope