To use the unit, the case head is first fit into the cartridge spindle, whose conical recess accepts heads of any size and centers them. Next, the ball knob and the attached bullet spindle are pulled to the right to insert the bullet tip into the spindle. The cradle is moved until the dial indicator tip compresses against the bullet just forward of the case mouth, the cartridge is rotated in the Tool, and the degree of runout is read off the dial. Cartridges with more than about 0.003 inches of variance should be culled for practice or sighting-in.
Correcting a misaligned bullet is also simple. The cartridge is rotated to put the “high point” of misalignment directly under the nylon-tipped straightening thumb screw, located directly opposite to the dial indicator tip. The screw is tightened against the bullet until the cartridge is straightened, as indicated by the dial indicator. The cartridge is then rotated again to determine how much runout still exists, and the process is repeated as necessary.
Testing with 6.5 Creedmoor and .308 Win. target rifles showed that cartridges with 0.002 inches or less runout grouped measurably better than those with 0.006 inches or more. Just as significantly, shooting tests at 600 yards showed that cartridges straightened with the Concentricity Tool produced none of the flyers experienced with unstraightened ammunition.
To be sure, correcting bullet misalignment will not produce the same performance improvement in all guns. However, any reasonably accurate rifle should group noticeably better with ammunition sorted and straightened in the Hornady Lock-N-Load Concentricity Tool, making it highly useful to precision shooters.
Suggested Retail Price: $127