Craftsmanship > Gun Building and Repair

Wyosmith Building Tutorial

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Wyoming Mike:
Now I am going to inlet the barrel channel.  I start by going half the depth of the side flats.  You make a shallow channel to the depth of half the height of the side flats.  On a swamped barrel such as this one, you go 1/2 the depth of the flat at the waist.  Then cross hatch it at about 1/8" increments with a chisel so you can cut paper thing shavings out of it to adjust the depth deeper toward the muzzle and the breach.  Keep your chisel like razors!  This is "channel A" from picture #13.

You have to get a bit deeper at 4" increments going towards the breach and the muzzle, as you start from the waist.  So, to recap, you cut "channel A" full length at the shallowest depth, and then gently deepen it as you cut to it's final depth.



 
These are my initial cuts to make "channel B" of picture #13  Again, I take the 1/2 diameter of the barrel at the waist of the barrel and make this channel that deep for it's full length.  Take pains with this!  You want to be very precise and use the side of a file and a scraper to make sure it's the correct depth at ever 3" increment for the full length of the barrel.  I do the procedure the same way as I did "Channel A".  1/2 the depth of the barrel at the waist, and then deepen it a bit at a time with files and scraper going towards the muzzle and then towards the breach.



 
This is the breach end and the roughed out "Channel B"
 


 
This is the breach end of the channel as it's almost done.



 
Now I take a 1/4" chisel and I rough out the "45s" (45 degree angles on the bottom of the octagon barrel channel)

Wyoming Mike:
Hi Steve.  Sorry, something came up so I have been a little slow.   Everything is back on an even keel now.  I put the rest of it up today or tomorrow.

Wyoming Mike:
Now I use my "secret" weapons - Gunline Octagon bedding tools. (you can buy then through Brownells)  

You have to use these tools to appreciate them.  However they are a bit pricey.  For building only a few guns you can do the same work with bent "foot rasps" which you can make out of mild steel and just make your own teeth with a 3 corner fail.  They don't work as easily as the Gunline tools, but they will get you through a barrel channel.  You just re-sharpen them with the file a few times per gun.



 
Here you can see the breach end is smoothed out with the gunline tool, and the bottom of the pic you can see the roughed out channel as it was left by the 1/4" chisel from Pic #19



 
Here you see the use of a steel rule.  Any straight non-flexing edge can be used.  I lay it along the bottom and the "45s" and see if it will rock.  Any rock shows you where the high spots are.  You file them down until you have no dips and humps, and you go SLOW so as to not take more than a very few thousandths of an inch in depth so the barrel will not be flexed at all when it's installed.






I now indicate where I will drill a 1/16th hole to make the center of the barrel channel  It will be the center of the rod channel later.  I will drill it PERPENDICULAR to the top edge of the stock so it comes out in the exact center underneath the barrel, and so it comes out at the "dogleg" where the rod will enter the handrail.



 
The barrel is coated with inletting black and the fit is checked and small areas are scraped and filed to insure a perfect fit.  Not that after the barrel is fitted for good I slab off the waste wood that was on the sides.



 
Now we breach the barrel.  The threaded hole and the threaded nose of the plug have to be the same depth/length.  This is a Colorain barrel, so it came to me breached, but if I were to do my own breaching I would first measure the hole with a depth gauge and either file the back of the barrel (if the hole was too deep) or the nose of the plug (if the nose was too long) until I had the correct length/depth relationship between the barrel and the plug.  

Then you screw in the plug and if the stampings of the barrel are showing you would figure out how much you would have to file off BOTH the barrel and the plug to turn them so the stampings are down.

The math is easy

Let's say we have a 3/4X16 thread.  There are 1000 thousandths in an inch, so 1000 divided by 16 = 62.5 Then you divide the 62.5 by 8 which equals 7.8.  For each flat you need to advance to hide the stamping you would file about .008" off both the breach plug nose and the barrel.  If you needed to go 1/4 turn it would be .014, and so on.

If you have 18 TPI the You would divide 1000 by 18 = 55.5   Divide that by 8 and we get 6.9 (close enough to .007 to call it that).  You'd file .007" for each flat you needed to advance.

Easy!




Here is the breached barrel, centered over the channel, and ready to inlet.

Make SURE that you keep the barrel to the rear and that the web of the breach plug, and the rear surface of the barrel are inlet tightly to the rear so you have solid wood to metal contact here.




Here is the breach plug inlet fully.

Wyoming Mike:
No problems.  Just heard from Bill on the next article.  I will post some today.  Send the rest if you have them.

Wyoming Mike:
Now I install the under lugs.  Make sure the spacing is correct, and that your underlugs don't interfere with the tabs on your rod pipes.  Lay out the spacing of both the pipes and the underlugs first, on the side of your stock, so you don't run into trouble later.
 
This shows an underlug laid on the barrel.  You scribe a line on both sides of the dovetail.


 
This shows a series of saw kerfs cut to the depth of the lug.  KEEP THE 2 OUTSIDE KERFS INSIDE THE 2 SCRIBE LINES about 1/32" so you don't cut away the female dovetail.


 
Now I set the barrel so the kerfs are even with the sides of the jaws of my vice.  I saw out the tabs of steel.  By setting the barrel this way in the vice, I cannot have the blade jump out of the cut and skid over the flat of the barrel.  not important for under lugs, but the same technique is used on sights, so it's a good drill to learn.  This keeps your flats nice, and unscarred.


 
Here I use a 3 corner file to smooth up the bottom and make the dovetail


 

I then take a Vernier Caliper and measure the dovetail section of the underlug.



 
I use the depth gauge to measure the depth of the female dovetail.


 

With most 3 corner files, the edges of the files are not super sharp, so I use my jewelers saw to undercut the dovetails to proper length, and slowly file the length wider and wider, until I have the fit I want.



 
Here you can see the way it should be when it's all filed to fit.


 

Here the underlug is driven into it's dovetail slot, and it's perfectly level to the bottom of the barrel flat.

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