Polygonal barrels

[JBlk]

Did they shoot a regular round ball with a patch in a barrel of this type or were the projectile the same shape as the bore?I also wonder how this barrel was made.

[T*O*F]

I assume you mean that the barrels were polygonally  rifled, not that the barrels were polygonally shaped.

[George Sutton]

Glock and H&K both use polygonal rifling in modern cartridge guns.

Centershot

[James Wilson Everett]

Guys,

I have rifled a "Whitworth" barrel - a 7 sided polygon rifled bore.  It was a lot more time consuming than the typical 7 round bottom grooves.  You have to remove a lot more metal!  It was fun and entertaining, but no advantage.  Oh, by the way, it was a pistol barrel.

Just used a different shaped cutter for the rifling head with wide, shallow teeth rather than the regular round topped teeth.  It was a lot longer to cut - it looked really neat and a good conversation piece - it did not shoot or load any differently than a regular barrel - probably I will not do it again.  I just used a regular patched ball, not a special bullet.

Jim

[doug]

    round elongate bullets shot from a Whitworth with heavy charges, will obturate into a shape that matches the bore.  I think that Whitworth made a polygon mold but I also suspect that it would have been hard to load after a few shots unless you cleaned the barrel with each shot

cheers Doug

[Bob Roller]

First thing,A MERRY CHRISTMAS to all on this forum.
Next,the hexagonal bore Whitworth did have fouling
problems and a hexagonal scraper was devised to
help with that problem.These barrels will work with
a grease grooved bullet but the weight should be 500
grains or more with about 90 grains of powder to make
it  upset properly and fill the bore.When these long bullets
swell up like that they also lose about 3/8 of an inch in
length.There are better,easier to manage rifling systems than
what Lynton McKenzie called the "Hopeless case Whitworth".

Bob Roller

[Dphariss]

Did they shoot a regular round ball with a patch in a barrel of this type or were the projectile the same shape as the bore?I also wonder how this barrel was made.

Unless its a later rifle turned round for a starter American rifles with bores like this recut 1803 Harpers Ferry used the round ball. Most rifles with a turned muzzle used a short cloth patched Picket bullet. Many early false muzzle rifles used the Picket as well. In the quest for LR accuracy these evolved into a rifle shooting a long, cylindrical paper patched bullet.
The British had a number of "fitted" bullet designs, in earlier rifles it was the result of the general insistence on using far too fast a twist in rifles using a RB that required this. The fitted bullet carried over into rifles using elongated bullets with various rifling designs, including the Whitworth. I believe the advantage to the Whitworth was that it did not require a false muzzle to produce usable accuracy.

Dan

OOPS

[Hungry Horse]

 The Confederacy found that the hexagonal molds for the Whitworth  came with their own set of problems. They quickly discovered that a heavy traditional bullet shot almost as well, and didn't wear the bore as much as the hex bullet.

                    Hungry Horse

[JBlk]

The rifle that I am talking about is a ML caplock made around the 1850s.The bore looks similar to the picture that Dpharass has posted.Was this supposed to be an improvement over a regular rifle barrel?Are these straight from the bore to the chamber, or do the have a twist to impart a spin on the projectile?The bore on this rifle is in the area of .036 to .038 caliber.If the barrel does have a twist in it then it had to be forge welded over a mandrel that had that shape before being twisted and then reheated after twisting to have the octagon shape hammered into the barrel.If that is the case , how did they ever get a straight barrel?How many gunsmiths used this type of barrels?Thanks for you input.

[Dphariss]

The rifle that I am talking about is a ML caplock made around the 1850s.The bore looks similar to the picture that Dpharass has posted.Was this supposed to be an improvement over a regular rifle barrel?Are these straight from the bore to the chamber, or do the have a twist to impart a spin on the projectile?The bore on this rifle is in the area of .036 to .038 caliber.If the barrel does have a twist in it then it had to be forge welded over a mandrel that had that shape before being twisted and then reheated after twisting to have the octagon shape hammered into the barrel.If that is the case , how did they ever get a straight barrel?How many gunsmiths used this type of barrels?Thanks for you input.

The rifling was cut into the barrel with a cutter after the barrel was reamed smooth.
By 1850 most rifle barrels were steel and Remington was a major supplier of blanks both simply drilled or complete rifled barrels.

Dan

[Daryl]

The rifling was cut into the barrel with a cutter after the barrel was reamed smooth.
By 1850 most rifle barrels were steel and Remington was a major supplier of blanks both simply drilled or complete rifled barrels.

Dan

Most or many of the finished barrels were turned for guide bullet or ball starters.

[Dphariss]

The rifling was cut into the barrel with a cutter after the barrel was reamed smooth.
By 1850 most rifle barrels were steel and Remington was a major supplier of blanks both simply drilled or complete rifled barrels.

Dan

Most or many of the finished barrels were turned for guide bullet or ball starters.

The cloth patched Picket was very popular in the east with LR target shooters and Schuetzen shooters everywhere as well. Both shot at ranges that would be difficult with a RB.
The false muzzle was invented for the picket but the desire for LR accuracy resulted in much faster rifling twists and long cylindrical bullets with paper patches by the Civil War. Pickets are undoubtedly the most finicky projectile for a ML.  A cylindrical bullet can be used without a starter of any kind and work darned good. A picket without a guide starter or a starter and false muzzle is a waste of time in my experience.
Dan

[FlyingZebra]

I have seen a few northern European caplock rifles with polygonal bores.
I used to own and shoot a British SxS caplock two-barreled pistol with polygonal bores, it shot well with tightly patched roundball, no fouling issues.
Also I currently own and shoot a 5-dram plus Westley Richards 16bore SxS rifle with Whitworth patent barrels (a cartridge rifle) that shoots well with ball just under groove diameter, over lubed felt wadding.
No outstanding fouling issues there either.





Cheers
John