The Hornady Lock-N-Load Modified Case in 6mm Creedmoor (Hornady part no. A6MMC) is a precision gauge accessory, not a live case. A fine thread locks it square onto Hornady’s Lock-N-Load Precision gauge, while the resized case neck lets a standard-diameter bullet slip in concentrically for a true reading. Handloaders use it to measure exact bullet seating depth against their own rifle’s throat instead of guessing from a load manual, which matters most for precision rifle and competition shooters chasing tight seating-depth tolerances. Find it in our reloading supplies lineup alongside the rest of Hornady’s measuring tools.

Key Specifications

• Ships at a listed weight of about 0.6 oz, light enough to add to any gauge or die order.
• Built for 6mm Creedmoor brass.
• Fine-thread attachment point locks the case perfectly square onto the Lock-N-Load Precision gauge.
• Neck is resized round and opened slightly so a standard-diameter bullet slips in concentrically, without binding.
• Delivers precise, repeatable alignment in your own rifle’s chamber for accurate seating-depth measurements.
• Pairs with the Hornady Lock-N-Load Precision gauge system — sold separately.
• Classified by Hornady as a Modified Case, a dedicated gauge accessory rather than a fireable case.
• Made from real brass, not a synthetic dummy round.
• Not loaded ammunition — an inert measuring accessory with no powder or primer, so it ships and stores like any other reloading tool.

Frequently Asked Questions

What is a Lock-N-Load Modified Case used for? It’s an inert gauge accessory that lets you measure bullet seating depth against your own rifle’s chamber, using Hornady’s Lock-N-Load O.A.L. Gauge or Precision gauge system.

What caliber is this modified case built for? It’s built for 6mm Creedmoor.

Is this a live, fireable case? No. It’s a dedicated gauge accessory — the neck and attachment thread are modified specifically for the gauge, not for firing.

Buy the Hornady Lock-N-Load Modified Case, 6mm Creedmoor

Order it from our Lubbock, Texas gun shop for fast, reliable shipping. Every caliber in Hornady’s Modified Case lineup is stocked together, so you can match your exact chambering.