Bolt Locking Lugs

[musketjon]

I have a 1916 BSA No1 MkIII* and the bolt number does not match. I was doing a bolt test last night and only one of the lugs is making contact. I haven't shimmed the offending lug yet to see how much gap is present. Is it ok to lightly stone the "high" lug until both get equal engagement? I know to only do a few light strokes and check. It's labor-intensive, I know. I just don't want to cut through the hardening on the lug. I know head space may be affected as well.
Thanks
Jon

Information

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[A square 10]

so homer told you to come here , im in for the ride , i need to know what advise you get ......

[musketjon]

Homer mentioned posting the question here but I'd already done that any way. The general concensus is to let a qualified gunsmith look at it before doing any thing to it unless I'm 110% sure of what I'm doing. First off, there are no qualified gun smiths in my area--Southern California is no longer gun-friendly and all the 'smiths got run out of town years ago. I've been a machinist/tool and die maker for the past 30 years so I feel confident that I can do the work mineself. I just have to keep reminding mineself to go SLOW and DELIBERATE and check, check, check the work after each 3 or 4 passes with the stone. I'll keep you posted on the outcome.
Jon

[muffett.2008]

Did you load up the bolt when checking, by using a fired case in the chamber to push the bolt back?
Check the stickies at the head of this forum, you should find one by Peter Laidler on bolt setup.

[Peter Laidler]

I agree with Muffer. Just read up all about fitting the bolt from an article I wrote some time ago. The bolt HAS to be stripped. pushed forwards and closed and THEN drawn back to test the witness marks. Read on and then read it again........... And then again.........

Hey ASquare, wondered where you'd been..........

[musketjon]

Thank you Mr Laidler. That was info that I absolutely did not know. I guess my homework isn't finished yet.
I just found your article on bolt fitting. That will be my evening read tonight. Thank you again, Sir.
Jon

[musketjon]

Took my SMLE to the range today. Inked the lugs before firing it. The lugs show even bearing on both sides. All is good.
Thanks again for all the input.
Jon

[musketjon]

After a range trip yesterday I need to move the front sight slightly. The group center is about 2-2 1/2 inches to the left of the bull. I know that with the M1 rifle at 100 yards, .008" equals a one-inch movement. What is the distance to move the No1 Mk III front sight blade to equal a one-inch movement at 100 yards? Yes, I know to move the front sight opposite.
Also, can the No1 Mk III sight blade be moved without removing the nose cap assembly?
Thanks
Jon

[Parashooter]

What is the distance to move the No1 Mk III front sight blade to equal a one-inch movement at 100 yards?

Sight radius in inches / 3600" = Sight movement for 1" POI change at 100 yards. Example: 24"/3600"=0.0066"

Or, for a quick and dirty calculation, just remember one-two-three-four -

For a one-minute change,
Measure the distance between the two sights,
Multiply that by three.
Move the decimal point four places to the left.

Example: 24" x 3 = 72", move decimal = .0072".

Close enough - and no calculator needed if you can multiply by 3. (This is actually a little trigonometry, since the tangent of one minute of angle is about .000291.)

[musketjon]

Thank you para shooter.
Jon