.300 Remington Ultra Magnum vs .300 Lapua Magnum
A to-scale size comparison of the .300 Remington Ultra Magnum and the .300 Lapua Magnum, drawn from SAAMI and C.I.P. cartridge dimensions and aligned at the case head.
.300 Remington Ultra Magnum (left) beside .300 Lapua Magnum (right), shown at the same scale.
The .300 Remington Ultra Magnum has an overall length of about 3.60″ with a 0.309″ bullet. The .300 Lapua Magnum runs about 3.72″ on a 0.308″ bullet. The two are close in overall length. See the full reference for each: .300 Remington Ultra Magnum and .300 Lapua Magnum.