6 GT vs .308 Winchester
A to-scale size comparison of the 6 GT and the .308 Winchester, drawn from SAAMI and C.I.P. cartridge dimensions and aligned at the case head.
6 GT (left) beside .308 Winchester (right), shown at the same scale.
The 6 GT has an overall length of about 2.64″ with a 0.243″ bullet. The .308 Winchester runs about 2.81″ on a 0.309″ bullet. That makes the .308 Winchester about 1.1x the overall length of the 6 GT. See the full reference for each: 6 GT and .308 Winchester.