William T. Watts
New member
I have a Scoot A Duff bore gauge for .308 barrels, I have checked dozens of barrels with the gauge and found few barrels that measure .300" at the muzzle, the largest was .3029. If the lands height of this barrel were .004" it means the barrel groove diameter was .3109", no way will this barrel group boat tail bullets, it may group a heavy flat base if the base is upset enough to seal the lands and grooves. The worst I've owned was a Savage, the rifle shot heavy boat tail bullets 180gr and up and flat base 165gr and up decently but anything lighter all over the paper. I contacted Savage about the problem and they didn't contact me until the following year wanting to know how the rifle was shooting, apparently they thought the rifle had been rebarreled. I shipped the rifle back and "supposedly" they replaced the barrel, when the rifle was returned I checked the bore and it measured "exactly" the same as when I shipped it to the factory. What I believe is no matter how bad a barrel is it usually is installed and shipped and we as consumers buy it and spend endless hours and money trying to find something it will group decently. I have one 30/06 rifle (Ruger Hawkeye) that has an ideal groove diameter .2998" that shoots lights out with 150gr and heavier bullets doesn't matter if they are flat base or boat tail. This is a subject rarely talked about but a major problem why many rifles will not group well."Considering all the issues with cartridges and all the compromises one has to make choosing one, the one that gives long barrel life, excellent accuracy, usability in all types of competition, ease of reloading, availability of good components and reloading tools, the .308 Winchester is best. A Kreiger 'tight' 26" 4 groove barrel with a 1:12 twist, .3075" groove and .298" bore will handle 168 to 190 grain bullets with excellent accuracy to 1000 yards."
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