1860 Army question

[Kaniksu Kid]

Why is the twist of an 1860 Army with the fluted cyl. opposite of all the other 1860s??
Can't figure this out.
Thanks,
KK

[Flint]

I replied on the SASS Forum with a list of twists of various models from a Colt's study by James Seven, circa 1958.

My opinion would be that as the tooling wore out, the new tooling was different.  Colt commissioned Eli Whitney to manufacture the 1847 Walker Dragoon, and the contract included that Colt would get the tooling as well as the guns, the presumption is that Colt would have a factory building to put the tooling in by the time the contract was completed.

At any rate, I would assume that Whitney's rifling equipment cut a right hand twist.  All the Colts pistols with a right hand twist were early production, later changed to left, and usually left hand progressive.

The early 1860's were semi-experimental, modifying the Navy frame to create them.  Perhaps in making the new barrels for the 1860 Army Colt was using older tooling in some back corner of the shop so as not to interfere with the production line that was cranking out Dragoons and Navies.

The other difference in the full fluted Army was the barrel length of 7-1/2 inches.  The  barrel for the unfluted 1860 was 8 inches long and left hand rifled.

With a solid barrel as the opentop Colt has, there is no torque factor to deal with, such as the possibility of the bullet rotation unscrewing a threaded barrel.  S&W had the problem, solved in earlier double actions with a cross pin, and in later revolvers by reversing the barrel thread.  There seems no functional difference in accuracy or other factors that would be affected by the direction of twist, other than perhaps the torque applied to the revolver in the hand upon firing, and that, depending on the shooter's grip and handedness could affect the POI as the revolver recoils against the hand and wrist, and twists against the thumb side or the finger side in a one handed grip.  I realize that this factor is only important with a heavy bullet in a large powerful cartridge.

[Mako]

Excellent answer

[Fox Creek Kid]

Also, on some of the very early original '60 Army Colts the chambers were straight bored & not tapered. These were accepted by the military & issued even though many had blown being "proofed" and before Colt had found a solution by using a tapered chamber. There was a great article on this a year or so ago in the "Man at Arms" journal. The reason why the military went ahead and took them was because of the political climate with imminent war on the horizon. Imagine being the lucky soldier being issued one of those "grenades"!!