Barrel steel can be made to levels of precision unknown to say, watchmakers, or brain surgeons. High end barrel steel is magnetically swept to find imperfections within the metal at the micron scale, which are rare to begin with after hammer-forging and rifling aligns the steel molecularly.
But it’s not perfection. No matter how well a barrel is made, it will have glitches, imperfections that cause it to flex more in some places than in others, imperfections that allow the barrel to twist and whip.
Now we’re not saying that an old Romanian PSL is any kind of example of precision engineering, but it is a great way to highlight barrel whipping, a phenomenon that happens to all barrels no matter how slightly.
One thing that can be done to a rifle barrel to improve its rigidity is to flute it. Not only does this improve its strength and lower its weight, it increases its surface area allowing it to cool faster and stay dense.
Oak Ridge National Laboratory has been working on another way to take advantage of fluting. They’re using it to house a tiny fiber optic cable array to pipe a laser around the barrel and assess the tiny deformations of the barrel as a bullet flies down it in real time.
Using the data from the previous shot, the attached computer goes ahead and re-sights the scope.
“When a weapon is sighted in, the aim point and bullet point of impact coincide,” said ORNL engineer Slobodan Rajic. “However, in the field, anything that comes into contact with the barrel [you know, bullets] can cause perturbation of the barrel and induce errors.
“The optical fibers are designed to split the laser beam twice, sending one beam along the top of the rifle barrel and another light beam along the side of the barrel, thus, we can measure both the vertical and horizontal barrel deflection.”
The adjustments made are in 1/1,000th of a minute of angle territory, which is inside of two inches a mile out.
Whether or not this is just a practical demo or a full-blown project to get the technology mated to barrels around the world, we like this technology. A lot. ‘Cause of the frikken’ lasers. Developments like these always find a place if not outright and for their intended purposes. Just you wait, we’re gonna see automatic sprinklers that are laser calibrated to keep the sidewalks dry, and microwaves that are laser calibrated to heat up more than just the ends of the burritos.
That’s a guarantee.