What difference does the groove count make in a barrel?

cornstalker

cornstalker

Active member
It's just a matter of time before I shoot the barrel out of my 6mm284. I am looking ahead to replacement and am thinking about buying a prefit Pac-Nor. They list 3,4,5,& 6 groove barrels.

Can someone explain the benefits/drawbacks of the various groove options to me?
 
Barrelmakers are really on top of their game these days, so the # of grooves has little to do with accuracy potential...
From what I understand, the same barrel rifled with fewer grooves will yield somewhat longer barrel life...
 
I have grown to love the 3 groove barrel for their lack of fouling, fastest barrels that I have ever had was with three groove barrels.

Lilja and Pac Nor three groove barrels have been real winners, and Pac Nor's barreling service is great.
 
well if your goin fast twist in a high intensity cartridge, go at least 4 grooves, I know a 3 groove 7 twist .257 barrel will rip the jackets off of 115 and 100 gr BT's launched at 3750 and 3900 fps. less bearing surface on the bullet equals more speed but hard on tender bullets.
RR
 
According to what I have recently learned from Kirby Allen from APS and Bryan Litz from Berger bullets, the three groove may indeed rip the bullet apart. They say it is the result of excessive "Bearing Surface Compression" resulting from more bearing surface.

Either way, sounds like a three groove is out for what I want to do. May look into a 4 groove or a 5R barrel.

If anyone cares to see the theories and statements I have referenced take a peek over on longrangehunting.com

As always, I appreciate everyone's input.

Thanks.
Chad

Link to LRH thread
 
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I have several 3 groove PacNor barrels in both 17 and 20 caliber, and they have all been excellent shooters, and they clean up extremely easily.

I generally don't spare the powder in those two calibers,and I have never had any problems with bullets coming apart as a result of the barrels.

Also, IIRC, 3 groove is all PacNor makes in their 20 caliber barrels. And I have never heard anyone complain about a PacNor 20 barrel in any way.

JMO - BCB
 
Like a guy said on 6mmbr.com today, "a good barrel is a good barrel". He was referring the thousands of barrels he has sold and couldn't say one configuration was better than another. I can't say through personal experience either, but I own one 3 groove and one in 5-C. Both barrels clean up nicely even after quite of few firings, and warm barrels. The canted land rifling is said to be more gentle on a bullet, but I cannot begin to understand what all happens to the bullet when its traveling down the tube.

3 groove rifling, there is more meat to each rifling, so it makes sense that they would reduce wear/erosion. I have also heard that cut rifling last longer to a comparable button pulled barrel. All major brands are putting out great barrels nowadays.
 
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I know a BUNCH of guys who swear by Pac Nor 3-groove tubes, and can assure you they run 'em hard. None have ever been known to try and conserve powder. Never heard a single bad word about them. The general concensus is "just as accurate, cleans easier, longer barrel life........"

I know Dan Lilja started making 3-groovers after Pac-Nor and won some competitions with them.......
 


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