7mm PRC vs 7mm-300 PRC
A to-scale size comparison of the 7mm PRC and the 7mm-300 PRC, drawn from SAAMI and C.I.P. cartridge dimensions and aligned at the case head.
7mm PRC (left) beside 7mm-300 PRC (right), shown at the same scale.
The 7mm PRC has an overall length of about 3.34″ with a 0.284″ bullet. The 7mm-300 PRC runs about 3.70″ on a 0.284″ bullet. That makes the 7mm-300 PRC about 1.1x the overall length of the 7mm PRC. See the full reference for each: 7mm PRC and 7mm-300 PRC.