Custom MkI Ruger with Octagon Barrel

[Rusty Marlin]

This was a two year project for me. Mostly because I don't have time to work on my own guns. So I'd do what I could when I had the time. I guess that's the good thing about being a manufacturing engineer, I plan processes out to the nth degree for a living, so with this one I could pick it up anytime and know exactly what was next. I'm a bit a nit when it comes to processing parts.

The barrel started as a 19" x 1.25 O.D. Anschutz rifle blank. Which was nipped off to around 8 3/4". The goal was to finish up at 8 1/4".
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1166.jpg

Set up in a four jaw, faced and 60 degree centers bored in.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1168.jpg

It was then turned between centers and threaded, leaving the breech end long for the feed ramp.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1180.jpg

The above image was the one posted in Thread Wires In Captivity. And when JCH commented on my unique octagon to round (latter pics) I thought I'd share this project on the gunsmithing board.

A test fit. Torque up and mill in the flats at BDC so the barreled assembly will fit the frame. These flats at BDC set the radial timing for ALL cuts to come.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1184.jpg

[Rusty Marlin]

http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1187.jpg

Leaving the barrel round until all breech work was complete allowed me to easily hold the barrel in a V block with out compensating for the taper that's in the Octagon. The Feed ramp was roughed out as a square tit.

Then the extractor clearance groove was milled in. But before I could mill in the groove I had to make an arbor for the 1 1/2" x .0625" carbide saw.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/arborparts.jpg
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/arborinuse.jpg

after the "level" work was done, the feed ramp was bored with a 1/4" ball end mill at 40 degrees.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/feedrampcloseup.jpg

[Rusty Marlin]

I rented a .22 Semi Auto Match chamber reamer, Bentz style, and reamed the chamber with the barrel hung off the back side of the mill table.

I didn't have a free floating reamer holder at this time and knew I could do it this way and be dead nuts perfect.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/chamberingsetup.jpg

Threaded it all together and test fired it. What a happy day that was! I put thirty rounds through it without a single hick up. All the important machining was spot on. Now it was on to the cosmetics.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1199.jpg

Unfortunately there are no photos of the octagon milling process, my wife visiting her family and had taken the camera with her. So basically a miracle occurred and it became octagon.

I would like to thank you JCH for noticing the distinctive way I chose to go from octagon to round. Its done with two cutters. One is the end mill that creates the flats, the flats are end cut, not profiled, this creates the undercut tips of the crown points. The second flat bottom end mill has the angle of the scallop ground in as a bevel.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1804.jpg

While was set up for octagon milling I also went around the end with a chamfer mill and cut in the bevels on the end. Making them deep enough that when the barrel was clamped in my spider and then placed in the four jaw chuck for boring the finished crown, that a .020 chamfer would remain around the edge of the flats.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1805.jpg

The front sight base is not integral. I don't feel my skills (or nerves) were quite ready for that yet. Its made from 1144SP and rests in a shallow pocket milled into the top flat parallel to the bore and is soft soldered in. There's enough surface area there it'll never come out without me removing it on purpose.

[Rusty Marlin]

Its made to except S&W style sight blades. If I ever decide I don't like the looks of the one that's there now, its a simple slide to the rear, tip up in the front and pull to change it out.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1807.jpg
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1813.jpg

The receiver tube and barrel were polished to 320 grit and Herter Express blued.
http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1812.jpg

http://i61.photobucket.com/albums/h45/rusty_marlin/ruger%20MKI/100_1819.jpg

[Ken_Shea]

Now if that does not get one pumped up better find another hobby.

Beautiful.

Thanks for sharing.

[Jim Shaper]

I had no idea the barrels were even threaded. That's awesome.

Makes me more hopeful to upgrade the barrel on my standard 5" mark 2.

[Cobbler]

Super fine work on that octagon. I really like the treatment at the transition from octagon to round.

[JCHannum]

Nice job Rusty, thanks for the detailed build photos. Not only have you built what should be a very accurate handgun, the details and octagon to round transition makes it a true one of a kind.

[MuellerNick]

I'm not into guns, but that octagon to round detail looks very nice.
Good job!


Nick

[Rusty Marlin]

Nice job Rusty, thanks for the detailed build photos. Not only have you built what should be a very accurate handgun, the details and octagon to round transition makes it a true one of a kind.

It shoots better than I can. I've since mounted a Burris Fastfire on top and at 30 to 40 paces its down right difficult to miss a 2" steel spinner offhand. :)
Groundhogs won't have a prayer! (insert evil maniacal laugh here) lol

Off a bench at 50ft it'll hold sub one-inch groups with Federal Gold Medal while looking over the irons. I want to repeat that test with the Reddot. I think it'll tight my group up even more.

I've looked at many photos over the years of octagon barrels, I'm a big fan of the classics, and can't recall ever seeing an octagon to round transition like mine. I truly hope it is a "one of a kind"; but realistically, doing anything stylistic that is new in the art of firearms is damned near impossible given the generations of artisans that have dedicated their lives making works of art from steel and walnut. I’m willing to bet I’ve got the only one in the neighborhood though. ;)

[Jim Shaper]

I've never seen anything like it either, and I agree it's beautiful!

[biometrics]

Nice Job! I really like the Round/Octagon transition!

[ulav8r]

That looks so good that I expect it wont be one of a kind for long.

[Smokedaddy]

Beautiful job and defiantly unique. Love them Rugers ...

http://i688.photobucket.com/albums/vv241/TheOriginalSquattingDog/VolquartsenV-6.jpg

-SD:

[Ausserdog]

Now that is down right inspiring, I like it. Very creative and nicely done!