Lakey on the First Pattern trigger 

To start this section off, I thought I would post some pictures of the first pattern trigger block with its combined sear hook.

These early triggers featured a deeply curved trigger blade with three deep grooves in its surface, for grip.These grooves were stopped in subsequent later trigger designs such as the safety sear model, presumably as a cost cutting measure.

Trigger adjustment was done by the use of a screw through the front of the trigger guard, the end of which bore against the front of the trigger immediately above the curved trigger blade. Turning this screw inwards progressively reduced the engagement of the sear hook onto the piston rod,thus lightening the trigger pull required to fire the gun.

It is rare to find a lot of wear on the sear hook, which shows the superior hardening techniques used on the steel during manufacture.

Only one pivot screw was needed for this style of trigger, so the early guns that featured this trigger only have a single hole trigger block.

Just above the rear curve of the trigger blade a shallow hole can be seen, this is the anchor point for the trigger spring. the other end of the coiled spring anchors into the trigger block.

All the best

Lakey

Open sights/aperture sights 

With thanks to Lakey.

Vintage B.S.A Air Rifle Open sights – Standard and Variations Part 1

When I first came into contact with vintage B.S.A Air Rifles, one of the things that impressed me the most was the quality of the open sights.

Here are a few photographs and brief descriptions of some of the sight variations on a few of my guns. The list is not complete, so there is more to come.

When Lincoln Jeffries invented his new air rifle, he clearly put a lot of thought into the open sights, and especially their design. In many ways a gun is only as good as its sights. And as Lincoln Jeffries, had designed his rifle as an accurate target arm, the sights had to be better than average in order to assist the shooter to realise the huge potential of the new design.

Firstly the foresight. It had to be seen in a wide variety of lighting conditions, such as out doors, or indoors under gas lamps etc etc. It also had to be capable of fine placement inside the ‘V’ of the rear sight, as all shooters show slight variations in the way they like their own sight ‘picture’ to be. Lincoln Jeffries settled on a small bead foresight, set upon a tapering base, which was dovetailed into the end of the barrel. Although very delicate, it allowed for very accurate shooting in a wide variety of conditions.

The rear sight which partnered the bead foresight was a very complicated affair for an air rifle. Most air rifles at this time (1904-5) still had a basic non-adjustable block rear sight, with a simple notch cut into its upper edge. Lincoln Jeffries realised that in order for his air rifle to be considered as an accurate contender to raise the sport of air rifle shooting from little more than a parlour game, into the national sport it later became, it would need to be totally re-designed and drastically improved. His new design consisted of a base block, together with a separate blade or leaf, which was raised and lowered by means of a central screw. If windage adjustment was required the sight could be tapped along its dovetail, either way to alter the fall of shot. Under the thumb screw there was a thin gauge spring steel butterfly spring which kept an even tension on the elevation screw, and stopped any unintentional movement.

Often these early guns were used as club guns, and so their sights were subjected to constant changing as different shooters wanted to make their own personal adjustments whenever they shot the gun. Such examples usually show well worn sights, which 100 years, and possible neglect along the way has not helped. Here is an example with a really worn rear sight, which is not uncommon.The sight has also lost its leaf spring. These are missing more often than not, due to the thin gauge and fragile nature of the spring.

The air rifle models that featured this first pattern of front and rear sight are

(1) H The Lincoln Air Rifle
(2) The BSA Air Rifle (Lincoln Jeffries patent)
(3) L The Lincoln Air Rifle
(4) The BSA Air Rifle
(5) The BSA Air Rifle (Improved Model B)

The next model of B.S.A Air Rifle, which was The BSA Air Rifle (Improved Model D), featured a larger front and rear sight. The foresight was marginally higher than the first pattern.

The rear sight was also larger. It was both wider and higher. Additionally, the elevation screw was made larger in diameter, which made it much easier to use than the first pattern sight. This new sight was called the number 10 rear sight.

Although the normal combination of sights on most B.S.A under lever rifles consisted of a bead foresight, teamed up with a wide ‘V’ rear sight, other combinations could be requested at time of ordering to suit individual shooters. These included a Blade foresight, teamed up with a notched rear sight

And you could also order other designs of foresight such as this barleycorn point.

You could even adapt your gun with a specialist target foresight such as this BSA No.19 Special tunnel foresight shown with a ring topped post. It was even mounted on a metal block to bring it up to the level of the number 8 aperture sight which was set into the ‘hand’ of the stock.

The number 10 rear sight lasted through the limited production during the First World, however the rear sight was changed again when the first post WW1 B.S.A Standards were produced.The post WW1 sights were higher still than the B.S.A Improved Model D sights. The rearsight was a very high turret style sight with a central elevation wheel, whilst the forsight on the new standards was the same bead style foresight but on a much longer stem.

More to follow in part two ........... watch this space

ATB

Lakey

Vintage BSA sights 

With thanks to Eddie.

BSA / Lincoln early guns had small, low profile sights, with the foresight generally being 0.450 in height, and with a "double" dovetail effect. Rearsight casting stamped "Pat. 460143" (as the later ones were too).

Rear dovetail widths on all patterns of sights run around 0.425-430" in my experience.

These front Lincoln / BSA "first pattern" foresights share the dovetail width of approx 0.274" with the later improved guns, and you sometimes see Lincolns / "The BSA rifle" early guns with these later foresights...they fit, but the cut-away for the sight base is exposed.

Improved guns had a larger version of the very early sight, this was 0.765" wide as opposed to 0.625 on the early guns, the vertical height of the base was basically the same though.

Apparently, around 1908, BSA were making a single shot rimfire rifle, and the larger, sturdy rearsight from this was used (possibly in modified form) on some of the .25 45.5" Improved guns.....this sight then was fitted to all the post WW1 Standard models, and possibly to some late Pre WW1 guns....I do not have an example, so cannot say for sure.

This rearsight (left) is much heavier in construction than the Improved sights, and used a coil spring to tension the insert, rather than the earlier, fragile stamped flat spring.

Also, Improved rear sight inserts are "L" section from above, and Standard "H" section.

Occasionally, one may come across a standard type rearsight, with graduations for the rimfire rifle it was intended for...I cannot believe the factory would do this, so maybe a period replacement?

Standard rearsights were graduated according to the pattern of gun they were fitted to, so a 45.5" gun will have 50 yards, a Light pattern 30 yards etc.

Foresights......Improved guns had several heights of foresight....they were all test fired at the factory, and perhaps this is why......or maybe because some guns I have will only zero at bell target range with a fine sight picture, you could specify a higher foresight for this discipline.....again, another mystery (standard unit to left in this pic).

Improved front sights have a 0.274" (ish) dovetail, and a height between 0.450" and 0.520".

Standard front sights have a 0.384" (ish) dovetail, and a height (normally) of 0.550"

Of course Standard in this context relates to post WW1 guns...at some time there will have possibly been a stage in production when old High front sights may have been used up....ie. The Improved Model D morphed into the Standard in a bit of a messy way, with some guns having the all wooden stock (ie. no butt plate, but the small oval trap), standard sights, but a roll impressed "improved model D" air chamber as they were built from old stock, apparently this went on till 1919/20.

All the above is from stuff I have personally encountered / measured, and from checking J.K.'s book for timelines etc.......believe me, this is far from a complete answer, but should help some.

<b><u>AN ADDENDUM BY JOHN MILEWSKI:</u></b>

Very good thread Ed and excellent illustrations.

The SMLE of the same period could be obtained with several different sizes of foresight and the numbers on these related to the height (in Imperial measurements) of the tip of the foresight to the centre of the bore. Could be the various numbers on BSA Air Rifles mean the same thing?

There are three specific patterns of backsight that BSA underlevers from 1905 to 1939 were fitted with. The First Pattern was only encounterd on the earliest rifles and had the small adjustment wheel. The second pattern was called the No10 by BSA and had a larger diameter wheel. They resemble an old "Cash Register" in profile. These were fitted to rifles made up to 1914.

The final Third pattern was the sight first fitted in 1919 and which remained the standard unit on post WW1 rifles. This is the sight on the left and top in Eddie's pics. This Third Pattern (I'm using italics as the reference to patterns is my own and not BSA's) has been encountered on pre 1914 rifles but I suspect in these cases, the sights are replacements. The Third Pattern was also fitted to the BSA No2 .22 Rimfire as Eddie has already said. The 1921 AG Parker catalogue describes the sight as being adjustable up to 200 yards and other than the ranges marked on the sight, it is identical to the unit fitted to the air rifle.

One "spanner in the works" to look out for is the inevitable Cadet major sight that can be made to fit a BSA underlever but is not correct to a pre war rifle of course.

Hope this helps.

1909 Mod D stripped to parts 

Thanks to Max for these pics:

You can buy vintage BSA and Lincoln spares 

from John Knibbs:

http://www.airgunspares.com/store/category/64/360/BSA/Std-%26-Light-Pattern/

http://www.airgunspares.com/store/category/64/360/BSA/Lincoln-Jeffries/

Chambers Gunmakers have a limited range of spares:

http://www.gunspares.co.uk/products/24301/Lincoln/

http://www.gunspares.co.uk/products/24296/Improved-Model-D/

http://www.gunspares.co.uk/products/24313/Standard/

Protek Supplies:

http://www.proteksupplies.co.uk/bsa-pre-war-cadet-and-cadet-major-parts.html