Hornady Lock-N-Load Headspace Gauge 5 Bushing Set with Comparator - Precision Reloading Tool

The Hornady Lock-N-Load Headspace Gauge 5 Bushing Set with Comparator is a precision reloading tool that lets you measure and control headspace on your handloaded ammunition. If you're serious about reloading—whether you're chasing accuracy at the range or building ammo that'll last through multiple firings—this gauge system helps you dial in your sizing dies and avoid the costly mistakes that come from oversizing brass. The comparator body attaches to your dial or digital caliper, so you can measure the distance from the case head to the datum line on the shoulder and track how your brass changes with each reload cycle.

Included five bushings cover most common bottleneck cartridges, from small-bore rounds like 17 Remington through the belted magnum family. That range means you won't need to swap systems when you reload different calibers—just swap the bushing. By catching headspace creep early, you extend brass life, improve chamber fit, and reduce the risk of pressure problems that sneak up when cases get oversized. It's the kind of control that separates casual reloaders from those who treat ammo development as seriously as their shooting.

The Lock-N-Load name is familiar to Hornady users—this tool carries the same practical design ethos: straightforward, reliable, and built to integrate with the rest of the Hornady reloading system. Whether you're sorting and prepping brass before the season or fine-tuning loads mid-season, having a repeatable way to measure headspace takes the guesswork out of die adjustment and keeps your ammo in spec.

Key Features

• Five bushing sizes for bottleneck cartridges (17 Remington through belted magnums)
• Comparator body attaches to dial or digital calipers for precise headspace measurement
• Measures case head to shoulder datum line to track brass wear and sizing
• Helps optimize sizing die adjustment for proper chamber fit
• Reduces oversizing and extends brass case life
• Prevents excessive headspace and associated pressure problems

Specifications

Brand	Hornady
Product Type	Headspace Gauge with Comparator
Included Bushings	5
Cartridge Compatibility	Bottleneck cartridges, 17 Remington through belted magnums
Measurement Method	Dial or digital caliper attachment

Frequently Asked Questions

What cartridges can I measure with this five-bushing set?

The five included bushings cover most bottleneck cartridges from 17 Remington through the belted magnum family. Check the Hornady Gauge Bushing Chart to confirm your specific caliber is included.

How do I use this headspace gauge for reloading?

Attach the comparator body to your dial or digital caliper, insert the correct bushing for your cartridge, seat the case against the datum line, and take a reading. Compare fired brass to sized brass to see if your die is sizing properly. This lets you adjust your sizing die to achieve the fit you want for your chamber.

What caliper do I need?

Any dial or digital caliper will work with the comparator body. You'll need to provide your own caliper—it is not included with this set.

Why does headspace control matter in reloading?

Oversizing cases creates excessive headspace, which shortens brass life, creates pressure inconsistencies, and increases wear on your firearm. By measuring headspace on fired and sized brass, you can adjust your sizing die to minimize growth and keep your ammo in proper spec longer, saving money and improving reliability.