Lyman 57 sight installation

tom unler · Sep 2, 2012

Greetings all,
I am hoping that someone out there in THR would happen to know the correct Tap and Pilot drill to use to install a Lyman 57EW on my Winchester 69A? The sight is in new condition, and the screws are original.

4v50 Gary · Sep 2, 2012

Outside diameter of the thread minus .01266 x % of thread depth/number of threads per inch equals hole diameter

That's the formula I found in Machine Tool Practices by Richard Kibbe (9th Ed, p 73)

Fleet · Sep 2, 2012

Figure the thread depth as 75% for that equation.

BBBBill · Sep 2, 2012

Does the package indicate what size the screws are?

Reloadron · Sep 2, 2012

This is the Destruction, err Instruction manual for the sight you have.

It tells you everything you need to know. Hopefully it will help.

Ron

tom unler · Sep 2, 2012

Found it...

Unfortunately, there is no package to read from, I would have done that first...

I searched the net a bit more and found 6-48 tap will do the trick~

Reloadron · Sep 2, 2012

tom unler said:
Unfortunately, there is no package to read from, I would have done that first...

I searched the net a bit more and found 6-48 tap will do the trick~

I linked to the Lyman instruction manual. That has the drill bit sizes and tap size. Should be everything you need to know. Not sure what you mean about a package to read from?

Ron

Lyman 57 sight installation

tom unler

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4v50 Gary

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Fleet

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BBBBill

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Reloadron

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tom unler

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Reloadron

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