Hornady Lock-N-Load Modified Case for 300 PRC Precision Rifle Cartridge (Model B300P)

The Hornady Lock-N-Load Modified Case for 300 PRC is a precision reloading accessory built specifically to work with Hornady's Lock-N-Load Precision gauges. If you're serious about long-range rifle handloading and need accurate overall length (O.A.L.) measurements for your 300 PRC ammunition, this modified case ensures you can dial in concentricity and case alignment that translates directly to repeatable chamber fit. The case threads directly onto Lock-N-Load gauges with fine-threaded engagement, keeping the case perfectly square during measurement—a critical step if you want your reloaded rounds to chamber consistently and shoot tight groups.

The neck of this modified case is machined perfectly round and opened slightly larger (.002" oversized) than standard to accept your actual loading bullets effortlessly and concentrically. That matters: when you measure O.A.L. with a bullet seated in the gauge, you're using the exact same bullet diameter you'll be loading, so your measurements are true to what your rifle chamber will actually see. This design detail is what allows the Lock-N-Load system to achieve its .001" O.A.L. accuracy. The case-head is threaded to attach to either Lock-N-Load O.A.L. gauge model, making it a versatile addition to any precision reloading bench.

Built to SAAMI specifications, this 300 PRC modified case is a consumable tool—you'll use it repeatedly as part of your gauge setup. It's not a loaded round or a standard case; it's a precision instrument for your reloading process. Keep one on hand so your O.A.L. measurements stay consistent from session to session.

Key Features

• Fine-threaded attachment to Lock-N-Load Precision gauges ensures perfect square alignment
• Perfectly round, oversized neck (.002" larger) accepts standard bullets concentrically
• Threaded case-head compatible with all Lock-N-Load O.A.L. gauge models
• Enables O.A.L. measurements accurate to .001" for consistent chamber fit
• Chambered specifically for 300 PRC ammunition
• Built to SAAMI specifications

Specifications

Frequently Asked Questions

Will this modified case work with my Lock-N-Load gauge?

Yes. The fine-threaded case-head is compatible with all Lock-N-Load O.A.L. gauge models. It threads on securely to keep the case perfectly square during measurement.

What bullets does this case accept?

The neck is oversized .002" to accept standard-diameter bullets intended for 300 PRC loads. You'll use the exact same bullet you plan to load in your ammunition, ensuring your O.A.L. measurement reflects real-world chamber fit.

Is this a loaded round or case I can fire?

No. This is a precision measuring tool for your reloading setup, not ammunition. It's designed to attach to your Lock-N-Load gauge for taking O.A.L. measurements. Dial calipers and O.A.L. gauge are sold separately.

How accurate are my O.A.L. measurements with this case?

The Lock-N-Load system, using this modified case, achieves O.A.L. accuracy to .001". That precision is possible because the case neck is machined round and the case threads square to the gauge every time.