Match/Varmint Contour
Descr.
MTU
Krieger Barrels Manufactures precision single-point cut-rifled barrels in calibers ranging from .20 through 4 Bore for the best target shooters and custom rifle builders in the world. They make barrels for almost any need including competition rifles, high-grade sporting rifles, high-power service rifle competition, AR-10, AR-15, ammunition test barrels and more.
They rifle all of our barrels using the single-point cut-rifling process. Although Krieger's machines are state-of-the-art, the process itself is the oldest and slowest method of rifling a barrel. It’s also the most accurate. The cutter removes approximately .0001 inch, or 1 ten-thousandth of an inch, at each pass, thus taking several hundred passes to rifle a barrel. This method produces almost perfect concentricity between bore and groove, a very uniform twist rate, and induces no stress into the steel that later has to be relieved. Along the same lines, they do absolutely no straightening of our barrels as this would only put stress right back into the steel.
Krieger's barrels are lapped after reaming to remove the tool marks, and then hand-lapped again after rifling. It has been said that if a barrel is cut-rifled correctly, it does not have to be finish lapped, and to some extent this is true. It should not have to be lapped to obtain uniformity of dimensions. This should come from the tooling and procedures used. But there is a slight improvement to the finish achieved by finish lapping, and the lay of the finish is now in the direction of the bullet travel so fouling is greatly reduced, and cleaning is made easier. It takes longer to finish lap, but they do it because it makes a better barrel. They are lapping to finishes under 16 micro-inch in the direction of the bullet travel. In contrast the government requires only a 32 micro-inch finish on its M-14 National Match barrels.
