Short answer: .308 Winchester is a .30 caliber rifle cartridge: a .308 inch bullet, loaded to a 62,000 psi maximum average pressure under SAAMI's standard. It hits much harder than 5.56: Hornady's 150 grain SST leaves a 24 inch test barrel at 2,820 fps with 2,649 ft-lb and still has 1,110 ft-lb at 500 yards, almost four times the 290 ft-lb a 55 grain 5.56 keeps there in Hornady's tables. It is used for deer and larger game, long-range target shooting and precision rifles. In the AR world it needs an AR-10 size rifle.
.308 Winchester vs 5.56: energy at the muzzle and 500 yards
| .308 Winchester | 5.56 / .223 | |
|---|---|---|
| Bullet | .308 in (.30 caliber) | .224 in |
| Max average pressure (SAAMI) | 62,000 psi | .223 Remington 55,000 psi; 5.56 Commercial 62,000 psi |
| Example muzzle velocity (Hornady) | 2,820 fps, 150 gr (24 in barrel) | 3,240 fps, 55 gr (20 in barrel) |
| Muzzle energy | 2,649 ft-lb | 1,282 ft-lb |
| Energy at 500 yd | 1,110 ft-lb | 290 ft-lb |
| AR platform | AR-10 | AR-15 |
Pressure figures are from SAAMI's Z299.4 standard; ballistics are Hornady's published data from our .308 ballistics chart and 5.56 ballistics chart. Test barrel lengths differ (24 vs 20 inches), and a shorter barrel is slower.
What caliber is a .308?
The ".308" is the bullet diameter in inches, which makes it a .30 caliber cartridge, the same bullet class as .30-06 and .300 Blackout. It is named for Winchester, the company behind it. Its military counterpart is 7.62x51mm NATO: 7.62 mm is the same .30 caliber and 51 mm is roughly the case length.
.308 vs 7.62x51
They are similar but not identical standards. SAAMI warns that military ammunition can run at different pressure from its commercial counterpart and that surplus military rifles can have headspace that suits military ammunition but is too much for SAAMI .308, naming 7.62x51 NATO and .308 Winchester as an example. Its advice: use military ammunition only in a rifle marked and chambered for it.
How far can a .308 shoot?
In Hornady's tables, a 168 grain ELD Match still carries 1,839 fps and 1,261 ft-lb at 500 yards and drops about 49 inches below a 200 yard zero. Usable range depends on the load, the barrel, the optic and the shooter more than on the cartridge alone; our .308 ballistics chart lists velocity, energy and drop to 500 yards for four loads.
What is .308 good for?
- Hunting: where the rules allow it. Colorado's deer rule (.24 caliber or larger, expanding bullets of 70 grains or more) is met by .308 hunting loads; Ohio makes necked cartridges like .308 unlawful for deer; Pennsylvania bans semi-automatic rifles, including AR-10s, for deer. See can you hunt with an AR-15 for the state details.
- Long-range and precision shooting: match loads such as the Federal Gold Medal 168 grain.
- AR builds: an AR-10 pattern rifle; many parts differ from an AR-15, see AR-10 vs AR-15 parts.
.308 ammo, with today's prices
Lowest price across the stores we track:
Hornady 150 gr SST .308 Win
Pros
- 2,820 fps from a 24 in test barrel
- Polymer-tipped hunting bullet
Cons
- Hunting bullet, not a match load
Hunting
Hornady BLACK 168 gr ELD Match .308 Win
Pros
- 1,261 ft-lb left at 500 yd
- Hornady publishes drop to 500 yd
Cons
- Match bullet
Long range
Federal Gold Medal 168 gr MatchKing .308 Win
Pros
- Match bullet
- Published to 500 yd
Cons
- Not a hunting bullet
Match
Federal Power-Shok 150 gr soft point .308 Win
Pros
- 2,820 fps published
- Soft-point hunting load
Cons
- Basic hunting bullet
Hunting basics
Compare all ammunition and lower receivers by price, and plan an AR-10 in the builder.
Frequently asked questions
What caliber is a .308?
.30 caliber: the bullet is .308 inch in diameter.
Is .308 the same as 7.62x51?
Close, but not identical standards. SAAMI says to use military 7.62x51 ammunition only in rifles marked for it, because military pressures and surplus rifle headspace can differ.
How far can a .308 shoot accurately?
It depends on the load, rifle and shooter. In Hornady's data a 168 grain ELD Match still has 1,839 fps and 1,261 ft-lb at 500 yards.
Is .308 more powerful than 5.56?
Yes. Hornady's 150 grain .308 has 2,649 ft-lb at the muzzle against 1,282 ft-lb for a 55 grain 5.56, and 1,110 against 290 ft-lb at 500 yards.
Can an AR-15 shoot .308?
No. .308 needs the larger AR-10 platform, with its own lower, upper, bolt carrier and magazines.
Is .308 good for deer?
With a suitable expanding bullet and where your state allows it. Ohio, for example, does not allow necked cartridges like .308 for deer.
