New project, coning a barrel

[Eric Krewson]

I have a re-bore that came out badly, I had a nice Rice .50 barrel and wanted to turn it into a .54 so I sent it to "the" guy, it was flawed when it came back. The bore was so tight I had to buy a .526 mold so I could start a ball with a patch thick enough so it wouldn't tear. Because the gun isn't a great shooter, I decided to open the bore so I could thumb start a .530 ball.

I bought a Joe Woods coning tool for a .54, today I decided to put it to use.

The first step is to disassemble the gun and un-breach the barrel, having the right tools helps.



I studied the instructions carefully, once I started there was no turning back.



The kit comes with a template to cut the various grits of wet or dry sand paper to hone the barrel, the sandpaper wears out quickly so I needed a lot of precut pieces backed with double sided carpet tape.



It took a few tries to correctly orientate the sandpaper on the tool. I used a large tap wrench to hold the tool.



And off we go; I rotated the tool clockwise and the barrel an equal number of times counter clockwise.



I will use 220 grit paper until the ball with a dry patch will thumb start halfway into the barrel. Here I am checking my progress.



This is a labor intensive job, my old arthritic hands said to stop after an hour or so, more to follow.

[Eric Krewson]

Like I said; the process is labor intensive, I am in my second hour, my 3M sandpaper had to be changed out often.



Done, most of the lands at the bore have been sanded away.

 

[JW_Halverson]

I have always been leery of coning a barrel because I can easily imagine myself applying uneven pressure and ending up with gun with a bad crown.

Let us know how it turns out!

[Eric Krewson]

The instructions specify that the barrel has to be held in the hands with opposing rotation and not in a vice to prevent an off-center cone. I didn't hardly put any pressure on the cutter, it feeds itself down the bore as it cuts with the 220-grit paper, the 400-grit sits in one place because it doesn't cut, only polishes.

[Eric Krewson]

Rifle testing today, I had coned the barrel with a Joe Woods coning tool in .54.



I could thumb start a .530 ball and a .018 all the way in easily, before coning I had to pound in a .526 ball with an .018 patch. With the cone I could seat the ball with minimum effort, I believe I could have gone to a .535 ball if I wanted to

I started shooting and wasn't doing too well, I was chasing balls with what turned out to be a fairly loose back sight. Somehow, I had bent the front sight, I straightened it several times before I was satisfied with it. I was hitting left and low at 50 yards and had already drifted my rear sight as far as I was comfortable with so I gave the front sight a slight tap.

I was shooting 80 gr of 2F and shooting low with about a 3" group at 50 yards, I had trouble seeing my front sight.

I decided to bump my load up to 85 gr, BINGO!

I had a shiny front sight for the high shot, the sun came out couldn't tell exactly where the blade was, I had a spray can of sight black so I sprayed the sight and took two more shots, I think I can live with the results.

[Eric Krewson]

Because the first barrel came out so well, I started coning barrel #2 yesterday. This one is a GM drop-in for a TC Hawkin, it is made out of much harder steel (1137) than the Rice barrel that I coned the first time. I have an hour into the project so far and can tell this coning job will take much longer than the first.

[Eric Krewson]

Done; this barrel was very rough inside so I gave it 50 strokes with a square pad of red scotch bright to hopefully polish up the burrs.



I have the lands looking like a mirror after the scrub, the grooves are still a little rough but much better than they were. I expect this barrel to be much slicker to load now.

A Teslong bore scope will drive you nuts with its clarity as shown in the picture.

[Eric Krewson]

If any of you have a barrel that is very hard to load after a shot to two a scotch bright pad scrub should fix the problem, it won't hurt the barrel.

Here is a how to; I did use a much smaller square than Mike did in the video, a larger one wouldn't start in my tight bore barrel, I used a .50 jag in my .54. For scrubbing other barrels, I have found that a jag one size smaller than your barrel bore size will work, I use a .45 jag in a .50 for a scrub. 

https://www.youtube.com/watch?v=vZyRD-iutus

[Stoker]

Thanks Eric for sharing this. I have a 50cal. that needs this. I'll check out the place you got yours from. Will try to find one in Canada first.
Leroy

[Emma Alva]

I anticipate that loading this barrel will be considerably smoother now.
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tiny fishing

[Eric Krewson]

As footnote; I decided to cone the two barrels a little deeper to put the ball at patch cutting depth, this was a mistake. I should have stuck to the directions that came with the tool which tell the user to stop coning when the ball is half way into the muzzle with a dry patch. Going deeper made my groups open up from 1" to almost 3" at 50 yards and required a long ball starter to get past the cone.

[sleek]

If you cut a little off the barrel will that tighten the group back up? Or do you have room with the site up front getting too close to the end?

[Eric Krewson]

I would have to cut 1/2" off the barrel, possibly an inch. On my Haines rifle this would amount to a lot of work, shortening the forearm, moving the nose cap and the ramrod pipes back.  As builder I could do this work but don't know if I want to, I could make the fix look like nothing had ever been done, fixing boo-boos is part of gun building, I made a lot early on so I have plenty of experience.

I over-crowned a GM barrel on a TC Hawken as well; this would be an easy fix to correct. In this case the barrel has never been a good shooter so I might not go to the trouble to cut the barrel off.

I have cut off a barrel before; I used a hack saw and a machinist's square and a variety of files, I made a special rig to re-crown the barrel that worked particularly well.

My crown cutting tool;