Straight Cut Rifling

[1LongRifleBoy]

Good Evening to all. I am exited to be a newcomer here and wanted to get some opinions regarding early rifling traits. I have recently acquired a flintlock long rifle of Pennsylvania make, 1825 or earlier and perhaps much earlier. It has a 45 caliber barrel of 44 inches length. I was intrigued upon examination of the bore to find that the rifling cuts are straight from breech to muzzle with no twist whatsoever. The cuts are shallow and with very minor rust I am thinking they were shallow when originally cut. I was aware that very early on smoothbores were made in this Pennsylvania long rifle style but was unaware that rifling cuts were made without any turning. As I think about it while a side to side spin seems best, even the over under spin I might expect from these straight cuts would create a spin perhaps adequate for a round ball? Hopefully some of you have seen this and can shed light on how common or rare this might have been at one time and in what time period it most likely may have occurred and if it was only a very early trait.

Many thanks!

[WESTbury]

Welcome to the ALR Forum.

Straight cut rifling is not that unusual.

Do a "Search" on this forum and you will see plenty of references to that style of rifling.

[Seth Isaacson]

Straight rifling was fairly common in muzzleloaders though not the norm by any means. In theory, they allow greater accuracy with round ball while still allowing the use of loose shot as well and possibly to shoot the latter better as well. If you search "straight rifling" on this forum, you should find multiple past discussions about it

[Bob Roller]

First of all,welcome to our forum and the only dumb questions are the unasked ones.Skill sets run from low to the stunning.Straight rifling  can be traced back to old Europe and one "story" says the spiral allowed someone to unknowingly firing the first accurate shot.There are barrel makers here that can make about any style or spiral wanted.We have shop owners that have only a few tools and others that are overloaded
and even Canadians that speak passable English and do superb work.I am now 2 weeks away from 87 and started into black powder in 1951 with a $20 purchase in a pawn shop.You will see long rifles referred to as SMR (Southern Mountain Rifles)and on the other end on the
other end some superbly crafted English sporting rifles in flint and caplock that show building skills that are rare but still here.
Bob Roller (Retired lock maker)

[Daryl]

Straight rifling, of course, imparts zero spin to the ball, in actual fact, makes it shoot like a knuckle ball (baseball term) At some point in time, probably due to a sprue (catching the wind) or maybe a destabilizing air void inside the ball, the ball will take on a spin like a curve ball (baseball term again) & curve out of the line of departure)point of aim).
This usually depends much upon the ball's velocity, to at which point downrange, the ball curves away. Suffice to say, straight rifling was slightly more accurate with a patched round ball, than a totally smoothly bored barrel. The advantage was that it could be used with fine shot for birds or small game, whereas a rifled bore did poorly with such.

[HIB]

Long Rifle Boy:      Simply as a point of information.    I have a straight cut rifle built by J. P. Becks son, Christian.  The gun appears to have been finished slightly prior to Christian moving north of Lebanon a few miles and opening his own shop in 1811 or there about.   The only advantage I can see with the straight cut over a smooth barrel is a slight improvement in accuracy plus the ability to load buck shot for big game and #4's for waterfowl.  The straight cut may keep the shot together longer for a tighter pattern at a longer range.   All, of course, depends on the load and how it is configured.

Welcome to the forum.   Excellent question.     HIB

[Mike Brooks]

Straight rifling is far more common in fowling guns than rifles. In my experience of course. Maybe I just look down more fowling barrels than rifles.

[1LongRifleBoy]

Much appreciate all of your replies regarding reasoning for straight cut rifling. All makes perfect sense. Sure happy to have connected with you all and to be a part of the forum.

Greg

[RAT]

I believe straight cut rifles served 2 purposes...

1. It allowed for increased fowling without adversely affecting loading. In other words, a fowled smoothbore might be harder to load after several shots due to fowling build-up. The straight grooves gave the fowling someplace to go.

2. You could load it like a rifle with a tight patch and ball, which wouldn't be so easy with a smoothbore. The rifling grooves gave a place for the patch to go. This would increase the gas seal effect of the greased patch. All of this, while at the same time, allowing shot to be used.