Winchester USA .223 Remington 55 Grain FMJ is a “white box” range load built for dependable cycling and consistent shot-to-shot performance in .223 Remington–chambered rifles. It uses a 55-grain full metal jacket bullet and a brass case, making it a common choice for training, drills, and general target shooting.
 
Key Features
Full metal jacket bullet – Designed for smooth feeding and consistent external ballistics, with no intended expansion.
Range-use focus – Tuned for reliable function and practical accuracy during high-volume sessions.
Cleaner-burning propellants – Intended to help reduce barrel fouling compared to older powder formulations.
Brass case – Supports dependable extraction and consistent chamber sealing.
Consistent loading standards – Built for repeatable ignition and velocity consistency during extended strings.
 
Specifications
Model number – W223K.
Cartridge – .223 Remington.
Bullet weight – 55 grain.
Bullet type – Full Metal Jacket (FMJ).
Listed muzzle velocity – 3,240 feet per second (varies by firearm and barrel length).
Listed muzzle energy – 1,282 foot-pounds (varies by firearm and barrel length).
Case material – Brass.
Primer type – Centerfire, non-corrosive.
Rounds per box – 20 cartridges.
 
Competing Items
Federal American Eagle .223 Rem 55 gr FMJ – Similar 55-grain FMJ training load in standard box formats.
PMC Bronze .223 Rem 55 gr FMJ-BT – Comparable brass-cased 55-grain FMJ option for range use.
Winchester USA Ready .223 Rem 55 gr FMJ – Higher-end training variant positioned above standard USA/White Box.
Remington UMC .223 Rem 55 gr FMJ – Direct alternative for general practice and drills.
 
Winchester USA .223 Remington 55 Grain FMJ is a straightforward, training-oriented .223 load designed around reliable function, predictable point-of-impact behavior, and typical “ball-style” performance for range work. Its 20-round box format and brass-cased construction make it well suited to routine practice and function testing.