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Merry Christmas to you all. I have mislaid my copy of Capt. Laidlers VULB and need some advice. Am I correct in saying that when you fit the scope onto a 4T you tighten the REAR screw first?. I have a Bren sling for it. Is there any 'Correct' way of fitting it or was that left to the individual user?
Thanks
If you're referring to the leather sling found on No.4(T) sniper rifles, there's an entry in the MKL, showing how to install the 1907 on a No.4(T).
1952 Instructional Pamphlet for No.4 Mk1(T) sniper rifle
Regards,
Doug
Re the sling. Even today the course are shown the methods of fitting as per the book but like the fitting of the butt length (spacers today of course) and hand stop, the sling is a matter of personal preference. The proof of the snipers preference being in the '.......scores on the doors' as they say, at the end of the course. But in real life, the instructors are always hovvering over you or just sat/squatting behind you as you are shooting and they'll offer advice if the fit isn't there or just ain't right.
Just as a bit of an aside. I used to go 'into the classroom' during the shoots and act as a student while the new instructors were doing their tutorial practices. Really just to shoot the L96 that I was about to acquire and have a go on the big .338 at someone elses expense of course. I thought I knew a lot about bog standard shooting but the instructors were always pretty good about personal preferences just so long as you were safe, observant and came up with the goods.
A good course - not that I ever completed one - and nice blokes although they were all a bit more ruthless at the end. Enough said there.............
Thanks for this but can I ask about fitting the bracket to the rifle? Is it tighten the REAR srew first? Or does it not matter?
Tighten the rear thumbscrew last.
Good Q Rob. Rear screw last. Tighten each up a turn or so at a time making sure that the last turn is to lock the rear thumbscrew.
I never really understood this course of action although I always followed it. It was SAID to be that this ensured that the telescope always matched the bore while setting up on the boresighting/calibration screen. But that is a bit of a myth in my experience because even when the rifle was locked up in the Enfield rest prior to accuracy testing one of the tests was to remove and replace the scope a couple of times to test for collimation within the set parameter. Regardless of which thumbscrew was tightened first or last, the tele would always collimate on the 28 foot screen. Anyone else any ideas as to why?
I do the rear last as I have a couple of rifles that are a bit worn at the spigot interface. Tightening the front first with the rear snugged allows me to push the front down better. Thus preventing or minimizing shifting under recoil. One rifle will put the second and following rounds about 2 MOA higher than the first round if not done in the above sequence.
We had a repair method for worn out front mounting spigots. Just a kinute....., I think I detail it in the little No4T book! It was very simple and gave lots of No4T's and L42's a new lease of life
Read about that ages ago in a little tome, but tramming everything in still gives me the heebie-jeebies. I've learned (the hard way more than once!) not to trust threaded hole locations except under loose tolerencing. Referencing off the unworn portion might do, but if the spigot's sheared off, then... At any rate, my L42s are far more gently treated than they were in service, so minor issues aren't a huge bother.Quote:
Originally Posted by Peter Laidler
FYI: The "No.4T An Armourer's Perspective" by Laidler/Skennerton is now out of print and sadly, there's no plan for more. I've just had more of the "Telescope No.32" booklets by Laidler printed and a large shipment is on the way to DS Solutions in England who are the only other place to get them. If you don't have a copy and plan on shooting and learning these telescopes, I highly recommend it.
How much are copies of the No 32 booklet Brian?
The price has increased to $20 per copy plus shipping of course.
Good observation JM> I know exactly what you're saying about boring/drilling through a threaded hole JM - and it's true. But the few .001" or so that the bore might be 'off' is easily catered for by a very slight adjustment in the slipping scale and the fact that the shaft of the rear thumbscrew is quite loose in the bracket. All that screw does is to pull the bracket down on a linear dovetail.
As per the procedure for tightening the front scope mount screw first and the rear last, this may relate to the standards of precision machine fixtures - where for an age the best practice multi-axis alignment hardware feature a “cylinder" and "diamond" location / lock feature for X and Y directions – they too are tightened cylinder first and then diamond.
In the case of the No4t the “cylinder” is the front mount screw position - actually used to load the end surfaces of the male and female cylinders into contact within the bracket and mount to establish the collimation of tube over barrel - X control - it can also act as a pivot point still around the axis of the cylinders.
The rear mount screw position feature the a rudimentary “diamond” geometry - the corner of the "diamond" being the male bracket features into the female vee-slot rear mount - tightening the rear mount screw last will the cause the vee faces to want to achieve even surface pressures from any alignment mismatch and will manifest as leverage acting around the front mount cylinders (pivot) to correct the Y alignment (achieve elevation zero)
So if you tighten the rear screw first you lock the elevation and then the front mount screw can only draw tight and not provide any pivot action - this way you risk losing a handful of millionths of elevation correction (0.0001" error approx .1 MOA) - Dirt, goo or sticky body fluids on these mount surfaces would also add to the error – play clean!
Also the same mechanics observed for building a function replica – front pad first – collimate the tube / barrel axles, then set the rear pad for elevation. I don’t mess with scopes much, but I would expect other mounting systems to work (best) the same way – get collimation first and then elevation…
I am prepared for minimal praise and maximum rollocking sir(s)!:cheers:
What about an "e-book" in that case? Or a DVD for that matter?Quote:
Originally Posted by Brian Dick
Ian Skennerton would have to make those decisions since he has the publishing rights. He still has some copies but you have to email him directly and they aren't $30 anymore.
I'm hoping Peter and Roger join forces and write a new one since we've all learned so much since the early 1990's. Hell, we're still learning!