Caliber debates are endless in the gun world. 9mm or .45? 5.56 or 7.62? Many arguments flare over bullet diameter, but one prominent disagreement is more about bullet and case length and powder reservoirs. The .308 Winchester and 30.06 Springfield are among the most prominent American hunting cartridges. Both also have military applications. They have essentially the same bullet diameter and have taken countless game animals. But is one better than the other? In the video below, Ron Spomer briefly takes on the 30.06 vs 308 dispute.
.308 vs. 30.06: Basically the Same Thing?
Many folks believe the .308 does exactly what the 30.06 does, it just comes in a smaller package. Ron says, “Not quite.” “The .308,” he says, “is a great little cartridge that just doesn’t quite live up to the hype that it sometimes gets. It really is not as fast or powerful as the 30.06.” Ron notes that you can see that by looking at them. The bullet diameter is essentially the same, but the 30.06’s longer cartridge case clearly holds more powder.
Ron says the most common argument for the .308 is that it generates a higher average chamber pressure than the 30.06: 62,000 psi to 60,000 psi. He allows the truth of that number but says the conclusion is inaccurate. “It doesn’t go just as fast, but it comes darn close,” depending mainly on bullet weight.
“Physics and Reality”
Ron illustrates his points by comparing bullet weights and velocity. He doesn’t discuss it, but he also gives us recoil foot/pounds too. All numbers are averages. Individual loads, whether factory or handloads, can and will differ.
.308 vs. 30.06: Factory Loads
One easy way to compare velocities is to look at various factory loads. .308 and 30.06 are both wildly popular, so everyone makes a variety of loads and bullet weights. Common weights begin at 125 grains and go up to about 180 grains. There are a few commercial 200-grain .308 loads and a few more for 30.06. There are some 220-grain 30.06 loads, but he’s never seen one for .308.
The only problem, as Ron points out, is that factory numbers are averages taken from test barrels. They may or may not be precise. They can and do vary by firearm and barrel. Using a chronograph is the only way to know for sure.
.308 vs. 30.06: Hand Loads
Handloaders, of course, have more flexibility. They can start with 100-grain plinkers and go all the way up to 230 grains and maybe even 250 grains in 30.06. Ron notes that 30.06 twist rates can handle those heavy bullets. Handloaders can also dial in their performance more accurately than factory loads.
Ron says he rarely sees a .308 bullet heavier than 200 grains. When he does, they are usually subsonic rounds. The 200-grain subsonic .308 is popular with feral hog hunters and has military applications. But if the .308 matches the 30.06’s power, why not go bigger?
Crunching the Numbers
Answering why .308 bullets don’t generally run as heavy as top-end 30.06 bullets brings us back to the case comparison. Heavier bullets gain their weight by being longer. The further those longer bullets extend into the powder reservoir, the less powder is available to push them. So, comparing .308 and 30.06 performance depends on balancing bullet weight and powder charge.
Ron consulted a handloader’s manual for his test numbers. He’s careful to say that individual handloads may vary, but the numbers he presents are solid averages representing the general performance of each cartridge. He compares numbers for 125, 150, 165-168, 180, 200, and 220-grain loads. He concludes that higher pressure does not necessarily equal greater velocity.
Here’s a quick breakdown of the numbers. We’ve shared Ron’s charts too.
- 125-grain bullet equals +125 fps for the 30.06. Ron notes that few people hunt with 125-grain bullets.
- 150-grain bullet equals +29 fps for the 30.06. Ron believes 150 grains is the optimal .308 load. He says that these numbers are close enough that the .308 is equal for all intents and purposes at 150 grains.
- 165-168 grain bullet equals +98 fps for the 30.06. Ron says this bullet weight is starting to be too much for the .308’s powder capacity. He also believes that this weight is optimal for the 30.06.
- 180-grain bullet equals +105 fps for the 30.06.
- 200-grain bullet equals +238 fps for the 30.06.
- 220-grain bullet equals +300 fps for the 30.06. Ron couldn’t find a factory 220-grain .308 load but found one handload value.
We can see that the 30.06 wins going away as the bullet weights increase and the 30.06’s larger powder reservoir kicks in.
The 30.06 is Clearly Faster
As Ron says, it’s physics. More powder kicks the bullet downrange faster, though the .308 can hang in the 150-grain range. Does that mean you should ditch the .308 for the 30.06? No. The .308 does many things very well. It’s popular for a reason.
Ron likes that the .308 cartridge fits short-action rifles whereas the 30.06 definitely does not. Cycling a short action doesn’t really make that much difference time-wise, but people like those actions. They’re comfortable and the rifles can be a bit more compact. Plus, you may save a little weight. If you like short actions, you’re not sacrificing much with the .308. The recoil numbers also favor the .308 as it’s going to be a little easier on your shoulder than the 30.06.
But if you’re a stickler for wringing the last little bit of performance from your .308 cartridge, you might prefer a 30.06. Ron says he sometimes thinks of the .308 as the “30.06 Short.” Both cartridges work beautifully. The faster bullets have drift and drop advantages, but that’s no secret. If you want to shoot heavier bullets, though, the 30.06 is the much better choice all around. We suggest you watch Ron’s full video. he touches on nuances we don’t cover here.
So, what do you think? Is one of these cartridges clearly superior? Does it depend on what you’re doing with it? Hit us up and tell us what YOU think in the comments. Happy shooting, y’all.
