Shorter caseFits a shorter, lighter action and a shorter powder column, which tends to burn more consistently.
Less bullet insideLong, sleek bullets sit farther out of the case instead of eating the powder space, so they fit standard magazines.
Wider or straighter bodyWSMs and PRCs use fatter heads. Creedmoors keep the .308 head size but use less body taper and a sharper shoulder.
No beltNewer magnums headspace on the shoulder instead of the old belt, which is easier on brass.
The classic.30-06 Springfield
- Introduced
- 1906
- Case length
- 2.494"
- Action
- Long action
→
Modern answer.308 Winchester
- Introduced
- 1952
- Case length
- 2.015"
- Action
- Short action
The original modern answer. Roughly 100 fps behind the .30-06 with most loads, from a shorter, lighter, stiffer action. It became the parent of a whole family of short-action rounds.
The classic.270 Winchester
- Introduced
- 1925
- Case length
- 2.540"
- Action
- Long action
→
Modern answer6.5 Creedmoor
- Introduced
- 2007
- Case length
- 1.920"
- Action
- Short action
Slower at the muzzle, but its long, high-BC bullets hold speed and fight wind better past about 400 yards, with noticeably less recoil.
The classic.270 Winchester
- Introduced
- 1925
- Case length
- 2.540"
- Action
- Long action
→
Modern answer.270 WSM
- Introduced
- 2002
- Case length
- 2.100"
- Action
- Short action · fat .535" head
A short, fat Winchester Short Magnum case that matches or beats .270 Win speed from a short action.
The classic.243 Winchester
- Introduced
- 1955
- Case length
- 2.045"
- Action
- Short action
→
Modern answer6mm Creedmoor
- Introduced
- 2017
- Case length
- 1.920"
- Action
- Short action
Same bullet size, but built around long, heavy-for-caliber 6mm bullets that the .243's case and twist weren't designed for.
The classic.243 Winchester
- Introduced
- 1955
- Case length
- 2.045"
- Action
- Short action
→
Modern answer6mm ARC
- Introduced
- 2020
- Case length
- 1.490"
- Action
- AR-15 size
Puts .243-class long-range bullets in an AR-15 magazine by using a very short, fat case.
The classic.264 Winchester Magnum
- Introduced
- 1959
- Case length
- 2.500"
- Action
- Long action · belted
→
Modern answer6.5 PRC
- Introduced
- 2018
- Case length
- 2.030"
- Action
- Short action · beltless
Magnum 6.5 speed from a short action, with no belt and a case built for long, high-BC bullets.
The classic7mm Remington Magnum
- Introduced
- 1962
- Case length
- 2.500"
- Action
- Long action · belted
→
Modern answer7mm PRC
- Introduced
- 2022
- Case length
- 2.280"
- Action
- Long action · beltless
Same bullet size and similar speed, but beltless and built to seat today's very long 7mm bullets without eating powder space.
The classic7mm Remington Magnum
- Introduced
- 1962
- Case length
- 2.500"
- Action
- Long action · belted
→
Modern answer7mm WSM
- Introduced
- 2002
- Case length
- 2.100"
- Action
- Short action · fat .535" head
Near-7mm Mag speed from a short, fat case in a short action.
The classic.300 Winchester Magnum
- Introduced
- 1963
- Case length
- 2.620"
- Action
- Long action · belted
→
Modern answer.300 WSM
- Introduced
- 2001
- Case length
- 2.100"
- Action
- Short action · fat .535" head
Close to .300 Win Mag speed with lighter bullets, from a short action. The original short-and-fat magnum.
The classic.300 Winchester Magnum
- Introduced
- 1963
- Case length
- 2.620"
- Action
- Long action · belted
→
Modern answer.300 PRC
- Introduced
- 2018
- Case length
- 2.580"
- Action
- Magnum action · beltless
Built for very heavy, long .30-cal bullets (around 225 gr) seated long, for extreme-range shooting.
The classic.375 H&H Magnum
- Introduced
- 1912
- Case length
- 2.850"
- Action
- Magnum-length action · belted
→
Modern answer.375 Ruger
- Introduced
- 2007
- Case length
- 2.580"
- Action
- Standard long action · beltless
Matches or beats the .375 H&H from a shorter case that fits a standard .30-06-length action, with no belt.
Case lengths are SAAMI maximums; years are when each round was introduced commercially. Performance comparisons are typical factory-load behavior, and your rifle and ammo will vary.