.223 Remington vs .243 Winchester
A to-scale size comparison of the .223 Remington and the .243 Winchester, drawn from SAAMI and C.I.P. cartridge dimensions and aligned at the case head.
.223 Remington (left) beside .243 Winchester (right), shown at the same scale.
The .223 Remington has an overall length of about 2.26″ with a 0.225″ bullet. The .243 Winchester runs about 2.71″ on a 0.243″ bullet. That makes the .243 Winchester about 1.2x the overall length of the .223 Remington. See the full reference for each: .223 Remington and .243 Winchester.