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Discussion Starter · #1 ·
Gentlemen,
I recently purchased a 1944 BSA No. 4 Mk 1 (T) with a No.32 MK II scope and was wondering if there is any preventative maintenance that needs to be done to the scope to prevent the "freezing" of the windage and elevation adjustments that I have heard of.Everything currently works quite fine at this time,But the scope shows no evidence of any prior service or repair (Mount screws still dimpled and unmessed with). I am ordering Mr. Laidlers book,But wanted to inquire with some of you folks as well. Thank you in advance!
 

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The Mk. II is not too bad for freezing up, but the Mk. III is horrible. The seals and the lub, plus a dissimulation of metal cause the Mk. III to seize tighter than a monkeys' ear. If you try and force it, you WILL shear off the lead screw. I've had a couple in for repairs where this has happened. Also the British discovered shellac on the threads as an early type of LOCTITE and when taking out the screws for the turrets it is not uncommon to have two or three of the eight screws twist off, requiring drilling, re-taping, and replacement of the BA screws. Drop me a line if you are having a problem.....
Cheers,
 

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Discussion Starter · #5 ·
Thank you for the addition information! I currently cycle the drums once a month to "excercise" them until I get some time to dispense some lead downrange.
 

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The MkI and II scopes are actually a lot less prone to this than the Mk3 because the contact area of the detent plunger ('clicker') with the hole it slides in is only about 10% of the Mk3 style. The reason they changed was the hardened steel Mk1/11 plunger has too small a contact area and tends to enlarge the unlined hole it slides in the brass 'turret', which creates slop ('backlash') in the adjustments. Peter Laidler's book has a drawing showing how Mk3 type plungers can be made up for Mk1/II scopes. A No6 straight flute reamer will usually make the holes true again, and then make up your plungers to suit.
 

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The Mk. II is not too bad for freezing up, but the Mk. III is horrible. The seals and the lub, plus a dissimulation of metal cause the Mk. III to seize tighter than a monkeys' ear. If you try and force it, you WILL shear off the lead screw. I've had a couple in for repairs where this has happened. Also the British discovered shellac on the threads as an early type of LOCTITE and when taking out the screws for the turrets it is not uncommon to have two or three of the eight screws twist off, requiring drilling, re-taping, and replacement of the BA screws. Drop me a line if you are having a problem.....
Cheers,

Would this apply to a Mk. II that has been updated with Mk. III turrets?

Thanks
Jay
 

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Yes, because it has the same plungers as the Mk1 and 2.

PM your address and I can send you a spare screw for that ring.
Ross280, thanks for the info and the offer on the screws, but I picked up 2 of them a couple of years ago.

Jay
 

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The seals on the Mk. III scope were one of the major problem for the turrets jamming along with the lubrication used. Mk. I did not have seals. The metal is also a problem and I've had some you had to use a press to press them apart to get the turret components out. Some Mk.I's that are badly worn from the plunger I ream and use a ball bearing and spring. Again, count on breaking off one or two of the turret screws...
 

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Shellac...

Doesn't shellac dissovle in paint stripper? What about the application of a little localised heat on the end of the screw itself to soften the shellac by conduction?

There must be an easier way than brute force to get the little sods out???
 
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