The Science Behind EABCO Accuracy Barrel Brand Rifle Barrels

Each and every one of our barrels is inspected, checked, and measured throughout our production process. Our barrels are not mass production items where maybe 1 out of 10 or 1 out of 100 gets inspected. Our bores are deep hole drilled on machinery that turns the barrel and keeps the drill stationary. This is the only way to assure the straightest hole... Which is especially critical for long lengths as in rifle barrels. After this, our bores are then reamed to within .0002" of exact bore dimension. That's not thousandths. It's TEN Thousandths. 2/10,000ths is the spec. This reaming removes all but the deepest drilling tool marks. Our barrels are then button rifled, which swages the rifling into the bore as it burnishes the remaining toolmarks. At this point the barrels are referred to as "blanks". They are about 1.25" in diameter and 29 inches long.

The blanks are cut to length before turning. This assures that the bore is centered at both ends when we do the actual contour turning. The next step is to clamp the barrels between centers and turn the contour. We have invested heavily in machinery that is custom built to our specifications. Massive tailstock and tailstock bearings to dampen vibration. Programmable steadyrests keep the center from flexing as the cutter moves down the length of the barrel. The result is the straightest possible barrel with the straightest possible bore.

From here, the barrel gets chambered with reamers that have fitted, free rotating pilots. They're mounted in a floating reamer fixture that follows the bore. There is no play or chatter and our chambers get reamed perfectly straight and perfectly centered, and perfectly aligned with the bore. We do a similar process at the other end to assure that the crown gets the same amount of perfection. - We intentionally do NOT lap our bores. First of all they do not need it because they are dimensionally consistent within .0002". Second of all we do not wish to introduce a potential fault into our process... Hand lapping can cause hourglass shaped bores. Third, lapping for cosmetics diminishes your precision to the depth of your deepest tool mark.