Pistol barrel from cutoff rifle barrel

[Steeltrap]

I have a leftover 12" piece of 45 caliber 7/8" octagon barrel that I plan on making a pistol with. I know the twist rate may not work well but I figure I'd build it, then shoot it to see how accurate it would be. If not accurate enough I'd have it bored to a 50 cal with a proper pistol twist rate.

The barrel is a straight octagon. I could just leave it that way or I could round and\or swamp the barrel (leaving say the first 4" octagon).

I do not have a lathe. So would it be foolish to even attempt rounding most of the barrel by hand, or is it cost effective to send it to someone who could round out the front?

Thanks

[2 shots]

 im guessing between cost of shipping and labor cost you would be in at the cost of a proper twist and profile  barrel.

[Hungry Horse]

 Once again the most important piece of information we would need to make a recommendation is missing, What is the twist rate??? If it is a faster twist than 1 in 48” bore it smooth and re-rifle it. If you’re planning of shooting light loads in it re-rifle it. But if you are willing to shoot it with light rifle loads, it will shoot fine.
 I have an old kit gun that I think was a clever way for the manufacturer to use up all the left over barrel stubs from building their rifles. It’s 45 caliber and 1 in 48” twist. It shoots great with about 40 grains of 3F in it.

Hungry Horse

[Steeltrap]

Twist is 1:60

[Daniel Coats]

You're better off buying a proper barrel to begin with.

[Daryl]

I would suggest 60" is just too slow for a .45 pistol. My 60" .54 does OK with 55gr. 3F. Kicks kinda like a S&W m29.

[D. Taylor Sapergia]

Ideal twist rate for a .45 cal round ball pistol is around 1:22".  Then 25 to 30 grains of 3Fg will shoot into a 25 cent piece at 25 yards from a rest.

[Steeltrap]

I was thinking since the twist is so slow, and the barrel only 12"....subtract .50" for the breech plug...that it's almost a smooth bore.

I have a 50 Cal pistol flintlock I built with a DeHass pistol barrel and I can't recall the rate of twist. It's obviously much faster than a 1:60 though.

[Daryl]

Mt .45 cal GM pistol specific barrel has an 18"twist. It shoots great with 25gr. of 3F  a .440" ball and 10 ounce denim patch.

[Steeltrap]

Well, nothing ventured, nothing gained. Since this piece was cut off a GM 7/8" rifle barrel and installing a breech plug could turn out to be a waste of time, I think I'll give it a try.

Pecatonica River sells pistol barrels from GM that are the same 7/8" full octagon but with a proper 1-20 twist. And those are 11"-12" in length.

So if the pistol shoots poorly with the cut off barrel, I could simply purchase a 7/8" full octagon and swap it out.

[Gtrubicon]

I would be interested in how it does. 0

[elk killer]

built several pistols from cut off rifle barrels, always found they shoot really quite well no matter the twist, using light powder charges
they work amazing well  unless your after one hole shot groups, i never was a paper puncher so i think you will be surprised

[Steeltrap]

Thanks EK. That's the information I was looking for. "Real" life shooting from one of these. Since this pistol is in .45 Cal. it's not legal for Pa. Deer hunting. So the plan is to just have it as a plinker and keep range skills up to snuff.

As for a range report, I don't plan on starting it until the snow flies.

[Hungry Horse]

 I think it all comes down to how much accuracy you are expecting, and what kind of shooting you will be doing. Paper punching might be a little disheartening, but steel changers of a reasonable size for pistols, at a reasonable range, might work fine. Oh, I disagree on the light loads in slow twist pistol barrels, in my experience the light load in a slow twist is about as accurate as spitting grapes.

Hungry Horse

[Jim S]

I built a mule ear pistol using a 10 inch piece of 36 cal. 1 in 48 twist barrel. The accuracy is ... crummy.

[Hungry Horse]

 How much powder are you shooting in it? Try doubling your standard pistol charge. One turn in forty eight inches is a pretty slow twist for even a rifle in .36 caliber so giving it a little more powder probably wouldn’t hurt.

Hungry Horse

[WadePatton]

Drill out the rifling. Problem with rate abolished. Use shot for snakes 

[Steeltrap]

I can tell you from personal experience that a short barrel shotgun has a very weak velocity. Shooting standard .410 shells from a T/C 45/410 barrel offered a starling killing range of 25 yards. Shot has small mass and needs velocity for effective penetration.

In other words a full concrete truck at 10 mph is much harder to stop than a bicycle at 10 mph.

[Jim S]

Hungry horse - I was using 25 grains of black powder with a pretty tight patch. I could try 30 or so.

[Daryl]

JimS I would expect 35gr. might be better yet.
Steeltrap, I  would expect 40 to 50gr. in the .45 with the GM 60" twist.
Slightly more powerful than an 1847 Walker (designed in '46).

[Jim S]

The weather was real nice today (not raining!) and I tried 28 grains. It did seem better, three shots about 3 inches center to center at 25 yards. That doesn't sound all that good, but a lot better than I done with it before.
35 grains in a 9 inch barrel seems like a lot, but I'll try it when I get another chance.

[Bob Roller]

The 54 caliber ball has the weight of the modern 44 caliber bullet.The recoil of the modern gun is abrupt.Big difference in performance too.
The weird shapes of some antique pistols ha fascinated me since I was 10 years old.Was it Manton that made a saw handle flint lock pistol that was a BIG step forward in the design of pistols in general regardless of origin.
Bob Roller

[Bob Gerard]

I filed an octagon CVA rifle barrel into a half- round pistol barrel for a Wheelock I built.  (I think I was about 25 years old or something). I left the bottom areas  that were not exposed alone, slightly tapered the rohnd barrel area and flared the muzzle a little, and filed grooves for copper wire inlays.
It would be great if it was bored out to a Smoothbore. It’s rather heavy.

[Daryl]

This pistol is TIGHT .54 (actually .53"), with a piece of 60" or maybe 66" twist rifle barrel. It shoots well with 55gr. 3F with a .526" pure lead ball and .020" patch.
I filed the octagonal barrel into tapered octagonal, then turned the rest of it to slightly swamped round. Taylor inlet everything for me as well as shaping the stock.
All I did was to "finish" it.

[Steeltrap]

Daryl,

Did you file the round part or do that on a lathe…or have someone else do it?

On Chambers website he shows his American Flintlock Pistol with a swamped octagon barrel. I was thinking I could swamp the 12” piece I have just using files. Since it’s a pistol length I don’t think that would be over burdensome.

And should it shoot really bad I could swap it with a true pistol twist octagon and either swamp that, or simply scrape the channel straight.