.223 / 5.56mm Once-Fired Reloading Brass for Sale

.223 / 5.56 Brass Processing

All of our .223 Remington and 5.56 NATO brass is sorted through multiple stages of automated and manual inspection. First, trommels remove rimfire cases, steel cases, and debris. Next, Roll Sorters separate cases by body and rim diameter, followed by SnapSorters that sort by case length. Finally, every batch is hand-inspected to remove damaged, defective, aluminum, or unwanted cases.

Depending on the selected product option, brass may then be cleaned using our industrial wet vibratory cleaning systems and dried in heated corncob media to improve appearance and remove residue.

To ensure customer satisfaction, every order includes approximately 2–3% additional brass to compensate for any unusable cases that may have escaped inspection.

Our once-fired .223 and 5.56 brass is a cost-effective choice for reloaders seeking quality rifle brass for target shooting, training, competition, or general-purpose ammunition production. Bulk quantities are available and qualify for tiered pricing discounts.

Learn more about the meaning of once-fired brass on our Brass Information page.

.223 Remington Reloading Specifications

For technical reference, SAAMI publishes dimensional and pressure specifications for .223 Remington cartridges and chambers.

View Official SAAMI .223 Remington Specifications

.223 / 5.56 Brass Specifications

.223 Remington vs 5.56 NATO Brass

.223 Remington and 5.56x45mm NATO use nearly identical external case dimensions, making the brass generally interchangeable for reloading when proper load development practices are followed.

Important differences reloaders should understand include:

• Many 5.56 NATO cases feature crimped primer pockets that must be swaged or reamed before installing a new primer.
• Military 5.56 brass is often slightly thicker than commercial .223 brass.
• Because of thicker case walls, some 5.56 brass may have slightly reduced internal case capacity.
• Case capacity varies by manufacturer and headstamp.
• Always begin with published starting loads and work up carefully when changing brass brands or case types.

Chamber Safety Information

.223 Remington ammunition can generally be fired safely in rifles chambered for 5.56 NATO. However, firing full-pressure 5.56 NATO ammunition in a rifle chambered exclusively for .223 Remington may create excessive chamber pressure due to chamber geometry differences.

Always verify the chamber designation marked on your firearm and follow the firearm manufacturer's recommendations.

Key Differences Between .223 and 5.56 Brass

• Primer Pocket: 5.56 brass commonly contains military primer crimps.
• Case Capacity: Military brass may have slightly reduced internal volume.
• Pressure Considerations: Reduced internal volume can affect load development.
• Headstamps: Many NATO-spec cases display the NATO cross-in-circle marking.
• Reloading Preparation: Military brass often requires additional primer pocket preparation.

Frequently Asked Questions About .223 and 5.56 Brass

Q: Is this .223 brass deprimed?
A: Unless specifically stated otherwise in the product option selected, the spent primer remains in place.

Q: Is this brass Boxer primed?
A: Yes. Our .223 and 5.56 brass uses Boxer primer pockets suitable for standard reloading equipment.

Q: Is the brass sorted by headstamp?
A: No. This is typically mixed-headstamp range brass unless otherwise stated.

Q: Can this brass be reloaded?
A: Yes. This brass is reloadable and includes approximately 2–3% additional brass to compensate for any unusable cases.

Q: What does once-fired brass mean?
A: Once-fired brass is an industry term indicating previously fired cartridge cases collected for resale. It does not necessarily guarantee a case has only been fired one time. Please see our Brass Information Page for a more detailed explanation.

Q: What is the difference between .223 Remington and 5.56 NATO brass?
A: The dimensions are nearly identical, but 5.56 brass often features thicker walls and crimped primer pockets that require additional preparation before reloading.

Q: Can I reload 5.56 brass using .223 load data?
A: Yes, but always begin with starting loads and work up carefully, as case capacity may vary between manufacturers and military versus commercial brass.

Q: Does 5.56 brass have crimped primers?
A: Many military 5.56 cases do. Commercial .223 brass is less likely to contain primer crimps.

Q: How can I tell if .223 or 5.56 brass has a primer crimp?
A: Military brass often displays a circular or staked crimp around the primer pocket. The crimp must typically be removed before seating a new primer.

Q: Do I need to swage 5.56 brass?
A: If the brass contains a military primer crimp, the primer pocket will typically need to be swaged or reamed before re-priming.

Q: Does .223 brass need to be trimmed? 
A: Yes, unlike many straight-wall pistol cartridges, .223 Remington and 5.56 NATO brass can lengthen during firing and resizing. Reloaders should periodically measure case length and trim brass as needed to maintain proper specifications.

Q: What is the maximum case length for .223 Remington brass?
A: SAAMI maximum case length for .223 Remington is 1.760 inches. Many reloaders trim cases to approximately 1.750 inches to maintain consistency.

Q: How many times can .223 brass be reloaded?
A: Reload life varies depending on chamber dimensions, load pressure, brass quality, and case preparation. Many reloaders obtain multiple reload cycles from properly maintained .223 Remington and 5.56 NATO brass.

Q: What primers are used in .223 brass?
A: Standard Small Rifle primers are typically used.

Q: How many .223 cases fit in a USPS Large Flat Rate Box?
A: Approximately 2,500 pieces fit comfortably, although higher quantities may fit depending on packing density.

Q: How many .223 cases fit in a 5-gallon bucket?
A: Approximately 3,800 cases.

Q: How much does 1,000 pieces of .223 brass weigh?
A: Approximately 14 pounds.

Q: Is Lake City 5.56 brass good for reloading?
A: Yes. Lake City brass is highly regarded among reloaders due to its consistency, durability, and availability.

Q: When is the best time to buy reloading supplies?
A: Historically, warmer months often provide better availability and pricing as overall reloading demand tends to decrease seasonally.