Fluting a barrel DOES NOT increase stiffness. A fluted barrel of the same diameter and contour as an unfluted barrel will be LESS stiff. However, when two barrels of the same weight (and length) are compared, the fluted barrel is stiffer (as it will have a greater diameter). Therefore, if you flute any given barrel, it will decrease in stiffness, however, it may be stiffer than another barrel of weight comparable to the fluted barrel.

An engineering analysis of barrel fluting and stiffness is presented on Varmint Al’s website at: http://www.varmintal.com/aflut.htm Note the conclusion: “The results show that a fluted barrel with the same weight as a solid barrel sags less from its own weight.”

From a barrelmaker’s perspective, there is another issue is associated with the fluting of barrels. As this process removes a significant amount of metal from the barrel, fluting has a tendency to open up the bore of the barrel in the vicinity of the fluting. If a barrel has been contoured, heat treated for stress relief and then hand lapped to the desired internal dimensions (as premium barrelmakers do), the fluting of a barrel AFTER these processes can (and usually does) significant alter the internal dimensions, possibly compromising the performance of the barrel. (Note that while changes in internal barrel dimensions can be measured in tenths of thousands of an inch, this can be quite significant with respect to the performance of match grade barrels.) To minimize and attenuate the effects of fluting it is recommended to: 1) have any barrel fluting performed BEFORE the barrel is hand lapped to final dimensions; 2) ensure the barrel fluting machining is performed slowly and with adequate fluid flow to keep the barrel cool at all times; and 3) do not flute the barrel within 3” to 4” of the intended location of the barrels’ muzzle.

Of course, this doesn’t really answer the question regarding accuracy loss in a hunting barrel, other than to point out that some weight savings without barrel stiffness loss can be gained by fluting, but that if not done extremely carefully, barrel integrity, and therefore precision performance can be compromised. One will note that despite a potential weight vs. stiffness advantage, fluted barrels are the exception in benchrest competition, where the highest levels of precision are demanded.