Author Topic: Armstrong correct rear sight  (Read 1971 times)

Offline Scota4570

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Armstrong correct rear sight
« on: April 09, 2015, 07:07:20 PM »
My build it a with a 13/16" barrel.  The cast sight I got is to large.  It is also type that sits on top of a dovetail in the barrel.  I feel I should make a smaller rear sight from scratch that sits in the dovetail and not on top of the barrel.  I also have it in my minds eye that the dove tail should be swaged instead of cut, allowing some material to sit proud of the barrel. 

Anyone have a picture of a real John Armstrong rear sight that I could use as a guide. 


Offline Acer Saccharum

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    • Thomas  A Curran
Re: Armstrong correct rear sight
« Reply #1 on: April 09, 2015, 07:34:56 PM »
Check the Library for Armstrong.

I cut dovetails with a hacksaw, stepping cut by cut over until almost wide enough. Cold chisel the fins left by sawing flush with bottom of dovetail. File base smooth. Then I take a SMALL chisel, and start stabbing in side-by-side blows for the actual dovetail part. This raises material on the barrel surface that you can dress up with a file, and it gives the undercut for your dovetail. But the raised metal is all steppy and rough, so I then use a big chisel to even up the cuts made by the small chisel. Alternate big chisel and 60 degree triangular file until the dovetail is clean and the width you want.

To try to raise the dovetails with big chisel alone is very stressful on a barrel.
« Last Edit: April 09, 2015, 07:35:48 PM by Acer Saccharum »
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Offline Scota4570

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Re: Armstrong correct rear sight
« Reply #2 on: April 09, 2015, 07:57:42 PM »
I do my dovetail on the mill.  I remove a rectangular slot of the right depth.  I then make the undercuts with a safe side 3-corner file.  Never could justify buying a dove tail cutter for the mill.  They are expensive and fragile.   

For this project I bought a dove tail chisel from track to make the undercuts.  I figure I would practice on some scrap barrel stock first.  Beating on a 13/16" 45 cal barrel does not seem to be a great idea to me either.