If a sling is made of hemp string, which has a lot of desireable qualities, (thin, strong, rigid, flexible) would untwisting of the string present a problem?

Might this rotate the pocket orientation, causing a non optimal release, or bullet orientation?

Materials that do not have this property:
Nylong rope, leather shoelace, braided materials.

Anyone else consider this as a factor in material choice?

I know this is not of historical significance, but my interest is more in ADVANCING the art, not only studying it.

Interesting query & wish I could offer an opinion.  

BUT I have noted that slings made with extremely flexible cords just dont seem to work as well as slings made with cords that have even a little length-wise and torsional stiffness.    This little bit of stiffness seems to be necessary for point-first pitches of ellipsoid glandes.

And I think the stiffer, the better, but I cant tell you why.

For sure, there is a place of diminishing returns because stiff cords also tend to be thick and have more air drag.

mgreenfield

This is a function of consruction rather than material. Twisted yarns are plied back on themselves to balance the tension, but will still carry residual twist. Often, humidity changes can alter the set. A poorly balanced/not relaxed yarn can twist and or kink back on itself.

You can cable a multi ply rope for even more stability. The easiet though is just to braid it. Braids are mechanically locked given a uniform twist yarn.

I agree with mgreenfield. I've always favoured slings with large torsional stiffness. Lengthwise may not be as important, but it sure makes the sling easier to handle. Maybe an ideal composite design would have a stiffer retention cord and a thin/flexible release?

Matthias

this is why my prefered cord is now the leather cord from old jump rope's it is about a 1/8 inch thick  really stiff does not twist and just delivers the power to that bullet. Not only that has a nice satifying snap at the end

I have used hemp before and when its woven it is great. I do not know about it unwinding - but I am also wary of it fraying after lots of use.

Twisting cords eh?  Well, I braid pretty much all my slings.  The twist and counter twist means that the cords never actually twist up themselves.