sine bar vs ye olde wooden thingy

[mattybock]

I don't know which is best for the use of rifling mild steel, so I'll hope someone has walked on this road before.
Seems that the modern gunsmiths love the ideal of a sine bar rifler. I have no flippity jibbin' idea how those things work, but I know they are adjustable for different twist rates.

Some folks like the wooden riflers that have a fixed rate on an 'inside out' rifle pattern.

My idea for a home rigged rifler would be to put my reamed barrel in a hollow metal lathe spindle at slow speed (c.2 or 5 rpm) and pull a non-rotating double toothed cutter through the barrel at a fixed speed, which would give me a spiral path in the bore.

So sounds best for those in the know ?
Sine bar vs. Olden woody thingy vs. Lathe rig?

And while I'm at it, does anyone know of any PDF file plans for a sine bar rifler?

 

[Keb]

I'm not familiar with either.

 

[wattlebuster]

 

[Dave K]

HUH? My English got misplaced.

 

[Rifleman1776]

There have been numerous illustrated articles on this subject in Muzzle Blasts over the years. Maybe someone saved some and can share.

 

[VTdeerhunter]

My understanding is that most barrel riflers (sine bar too) hold the barrel fixed and rotate the cutter. Your home made lathe rig sounds like just the opposite....it could work just fine, but is not the norm

 

[Paul R]

All you have to do is find a lathe that can be geared for 1/70th thread per inch.

 

[ohio ramrod]

The Henry Ford museam in Deerborn has a sine bar rifler. Another simple "home made " rifler is to take a long 3/8 square bar. Carefully twist it the desired twist and pull it through a block with a slightly oversized 3/8 square notch in it. There was a write up a few years back in muzzle blasts that showed the details. :idunno:

 

[Bruce Bogart]

Square rod style rifler. Still have yet to use it. Can't find reasonably priced smoothbore barrels to experiment with.

 

[Zonie]

What establishes the twist on your rifling machine?

Is the square shank that the handle connects to twisted to cause the rotation of the cutter?

 

[mattybock]

One of the things that makes me a bit wary of the old fashioned riflers was a bit from the film 'Colonial Gunsmith'. The smith and his helper were pulling like mad trying to get the rifler through the full length of the barrel. It was hard work.

ps, even consider just making your own barrel from bar stock?

 

[Bruce Bogart]

Zonie the square bar is twisted, which when pulled thru the guide imparts the twist to the rifling head. Did I explain that clearly :hmm: ? I've been told a BIG vise mounted securly somewhere and and huge pipe wrench can twist the square bar into any R.O.T. that is desired.

Matty, no interest in machining or blacksmithing my own barrel blanks.

 

[John Taylor]

My machine has a sine bar so I can very the twist from about 1 in 8" to strait. I tried the twisted square stock and spiral cut shaft. The barrel does not move while cutting but rotates for indexing.
Another way to make a lathe work is to use a cable and pulleys and a round disc with a circumference to match the rate of twist you want and thick enough to wrap the cable around. Mount the disc to the spindle and the cable to the carriage so the spindle rotates as the carriage moves, using a couple pulleys to get the cable to go the direction you want. You will also need a pulley at the end of the ways for the return. If you want another twist just make up a different size disk.

 

[bob308]

the one is called a sine bar machine the other a guide machine. you can change rate of twist by making differint guides. which means you have alot of extra parts standing around. i have a sine bar machine made it my self.

now the lathe idea i don't think it will work too good. and a boubble headed cutter no way.

harry pope rifled in a lathe but it was converted to a sine bar machine. so the head stock was locked and the carrage moved.

 

[juancho]

Many years ago , a guy I knew, made the guides by twisting a square bar inside a pipe to keep them straigt. What he found is that most ended up with a gain twist rather than a uniform twist.
The cutting head was a "holder" made of wood with a slot in wich he put a small piece of a round file.Adding small strips of paper under the file to get the desired depth of the groove , and lead lapping to finish it of.

 

[izzyjoe]

with 1-70" twist the square bar would'nt have to be twisted much. cause the rifling only makes a half turn in 35". so would'nt it only need to be twisted half way, 180 dergee to be exact.