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Thread: Polygonal rifling?

  1. #1
    Boolit Master andym79's Avatar
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    Polygonal rifling?

    Hi guys, I have been offered a Polygonal Pac-Nor barrel for a reasonable price.

    I understand the difference between Polygonal and standard rifling, but what kind of accuracy can you expect from a Polygonal barrel vs a standard rifled barrel.

    Specifically in a 224 1:8?

    Thanks

  2. #2
    Boolit Master andym79's Avatar
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    Further information of what I am using it for, this will be my first non cast rifle.

    The barrel is intended for a scope single shot. I plan on using 22 Cal (.224) 68 grain HPBT Match bullets by Hornady.

    I saw this posted on another forum "Lothar Walther will sell you a "polygonal" rifled barrel for various guns or a blank that can be made to suit about anything. Once upon a time, they conceded that the polygonal would be slightly less accurate than conventional land and groove but would last longer. I doubt it would be enough to matter in a service or hunting rifle."

    I have also read that unlike HK and Walther, Pac-Nor polgonal barrels are not truly polygonal but rather of a canted land type like a 5R, does anyone know if that is true?

    Are Polygonal less accurate I wonder?

    Essentially my dilemma is Pac-nor 1:8 poly vs Krieger 1:7.7 4 groove, the second costing $100 more. What do you guys think any advise is greatly appreciated.
    Last edited by andym79; 10-06-2017 at 05:16 PM.

  3. #3
    Boolit Master

    lefty o's Avatar
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    polygonal is every bit as accurate as cut rifling. i have 2 pac-nor polygonal barrels, and they are polygonal nothing like a 5r etc. between pac-nor and krieger, buy whichever tickles your fancy as they both make excellent barrels.

  4. #4
    Boolit Master andym79's Avatar
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    Okay so they are true polygonal like HK rather a 5r type?

  5. #5
    Boolit Master

    Rcmaveric's Avatar
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    I am not sure and I use a polygonal barrel in my 6.5 Grendel Black Hole weaponry AR barrel. Its just as accurate as any other gun. Theory is, its generates slightly higher velocities due to less resistance of riffling cutting in and better pressure seal due to riffling being more circular. That's about the jist of it. I can blow out bullseyes at 100 yards with Jacket bullets. Still tuning cast loads but I am on the right track as of now. I can guarantee its way easier to clean out leading though.
    "Speak softly and carry a big stick; you will go far."
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  6. #6
    Boolit Master

    lefty o's Avatar
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    Quote Originally Posted by Rcmaveric View Post
    I am not sure and I use a polygonal barrel in my 6.5 Grendel Black Hole weaponry AR barrel. Its just as accurate as any other gun. Theory is, its generates slightly higher velocities due to less resistance of riffling cutting in and better pressure seal due to riffling being more circular. That's about the jist of it. I can blow out bullseyes at 100 yards with Jacket bullets. Still tuning cast loads but I am on the right track as of now. I can guarantee its way easier to clean out leading though.
    thats about it. when i was shopping i spoke to the head dude at pac-nor, and his words were "sometimes you get a few more fps with the polygonal". i think they clean easier than cut rifles, but that may be affected by they are handlapped supermatch barrels.

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BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
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GC Gas Check