Polygon rifling

[kimberacp]

I noticed on Gun Broker, an upper for sale with a 18" mid-length barrel from Black Hole Weaponary, using Polygon Rifling.

Has anyone heard of this type of rifling for AR's or have a comment about the company?

Glocks use Polygon rifling but how good is it for rifle barrels?

thanks

[Cap]

Noveske uses it as well. I believe they get their blanks from the same place.

[bgary]

The theory is that polygonal rifling deforms the bullet less (no "sharp edges" digging into the bullet jacket), and better gas-seal.

ymmv.

[Graham Smith]

Possibly, less copper fouling, like the 5R barrels?

[mpeltier]

I had a BH 18" in one of my game guns for a while. It shot very good.

As to the pollygonal rifling, I have heard all the marketing yada yada about it. My opinion is it must be a less expensive method to rifle a bbl, but not any better than conventional lands and grooves.

[supreme135]

Polygon Rifling is used in making machinegun barrels. It's very tough for wear. Noveske I think is getting there blanks from Pacnor..

[supreme135]

I have a Noveske and Black hole barrel, they both are Polygon rifling and both shoot very well.