Hornady Lock-N-Load Modified Case .458 Lott

Precision Seating Depth Measurement

The relationship between bullet seating depth and the distance to the rifling—what shooters call "jump"—is fundamental to accuracy. Even a few thousandths of an inch can separate mediocre groups from genuine tack-driver performance.

How It Works

The Hornady Lock-N-Load O.A.L. Gauge is the industry standard for measuring this critical dimension. This modified case is the essential component that makes the system work:

• Threaded design attaches securely to the gauge body
• .002" oversized neck accepts your actual bullets—not simulated shapes
• Precision-prepared for accuracy to .001" tolerance
• Cartridge-specific for .458 Lott chamberings

Why This Matters

Unlike competitive products that use arbitrary bullet simulators, this modified case accepts the exact bullets you'll be loading. This means your measurements reflect real-world seating depth, giving you the precision data needed to optimize accuracy. Once you've established your optimal O.A.L., you can load with confidence that your ammunition will perform as intended.

The Result

Consistent, repeatable seating depth measurements that translate directly to improved accuracy and more predictable ballistics downrange.