224 Valkyrie
Since 1976

Unprimed Brass Cases

5.56x45mm Brass (Small Rifle primer)

5.56, 5.56mm NATO, 5.56x45
1.745 - 1.750 O.A.L.

The 5.56x45mm NATO is the military version of the .223 Remington, which is one of the most widely used centerfire cartridges today. Starline’s 5.56x45mm brass is identical to Starline’s .223 Remington brass except for a slight change in the metallurgy making it harder at the base of the case.

When loaded at .223 Remington pressures, Starline's .223 brass is safe to use in any firearm chambered for .223 or 5.56x45mm. If loaded to 5.56 pressures, you need to use firearms labeled for use with 5.56mm. It can be unsafe to fire 5.56mm ammunition in firearms with a .223 Remington chamber.

Status: Available Now

Box of
5.56x45mm Brass

*Starline Brass does not sell any loaded ammunition. What you are purchasing are brass cases only and will need to be loaded into ammunition in order to be fired from a firearm.


Overall Rating
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Reviews: 1
William D of Okeechobee, Florida
5 Stars5 Stars5 Stars5 Stars5 Stars
Last year Star-line sent me a sample of the new 223 REM brass. The brass was excellent. Primer pockets were uniform. OAL was excellent so there was no work involved in the primer pocket or trim length. The brass was within spec and could be loaded out of the box. Of course that is never recommended. Fully size all new brass for a semi or auto loading rifles or pistols. I expressed my concerns over the lack of a 5.56 NATO stamp, as probably others did also. Star-Line has responded. No longer will I need to mix and match head stamps. I now can count on using one and only one brass for my AR's. Availability of a high quality brass at a cost effective price no longer a issue. In many ways this brass rivaled Lapua at 1/3 the cost. Thank You Star-Line. Will