Polygonal Rifling for a Rifle Barrel?

[.30/30 Guy]

How good or bad is polygontal rifling for a rifle barrel?

What are your thoughts and experience with the polygontal for a rifle barrel?

Thanks

[Wayne Smith]

Well, the original Whitworth was a polygonal rifled barrel. Confederate snipers seemed to do well with it.

[Bullshop]

I had a 22/250 with Walther 6.5" twist polygonal barrel. The idea I had was that it should provide longer strings of accurate fire over conventional rifling due to fouling.
I was shooting 90gn Bergers and it was very accurate. I could never afford to proove it but I believe it helped.

[runfiverun]

anything that deforms the jaxket,or the bullets shape less should shoot better. [i definatly think it helps terminal performance on game]
at least that was marlins claim to fame with the microgroove bbl.
it seems to me you'd have some gas blow by,and lower velocity's from the hexagonal bbl though.

[geargnasher]

Excellent question. I'm shopping ideas for a new build and had the same question: What about polygonal rifling for CAST BOOLITS? Wouldn't that reduce shear stress on the land engraves and actually increase torsional bearing surface? Splines are strong, but only if you have a whole bunch of them.

Gear

[.30/30 Guy]

The Springfield O3A3 2 groove barrels seem to do very well with cast. They must be deforming the boolit quite a bit.

I am not looking for lower velocities. Looking in the range of 2000 fps in .30 caliber.

[runfiverun]

i really wonder how a 8, 12 or 16 sided bbl would do.
something different anyway.
you might just oversome stripping issues by not having lands.

[geargnasher]

I was thinking seven sides, or nine.

Also thinking of high velocity, much higher than 2,000 FPS, and a twist no slower than 12".

Gear

[runfiverun]

this would sure change the way boolits were shaped.
eliminate small drive bands,
truncated cone noses.

i wonder how a p/p would work...