.308 Versus .30-06
Q: How does the .308 Win. compare with the .30-06 for big game hunting? I was going to buy a .308 for deer hunting, but all my mates rubbished my choice as they all own .30-06s. What margin of performance does the .30-06 have over the .308? Which calibre would you prefer for all of our deer species and a proposed trip to Namibia for a plains game hunt?
Arthur (Buck) Jones
A: Although factory ammo for the two cartridges have very similar velocities, this doesn't apply to handloaded ammunition. Case capacity in grains of water is 56gn for the .308 against 68gn for the .30-06. Checking my log, I find that when both rounds are reloaded with the popular 150gn bullet the .30-06 has an edge of 200fps. My top load of 56gn of W-760 in the .308 drives the 150gn bullet at 2920fps, while 66gn of Re-22 in the '06 boosts velocity to 3105fps. But the .30-06 offers an even bigger advantage with 180gn bullets to be used on big game. It is hard to exceed 2650fps with the 180gn bullet in the .308, even in a 24in. barrel. Loading 60gn of Re-22 behind the 180gn Nosler Partition in the .30-06 gets 2900fps and velocity, energy loss and drop at ranges out to 400yd. are way less than what the .308 can do. The 180gn bullet has the advantage of extra weight for shock and tissue disruption. Sighted-in 3in. high at 100yd. the 180gn Partition is 4in. high at 200, down 2in. at 300 and 14 in. at 400. Factory ballistics don't bear this out because the .30-06 is badly underloaded at the factory on account of some of the old rifles which are chambered for it. In fact, I experienced no difficulty in driving the 180gn bullet in the '06 to 2800 - 2900 fps using slow powders like RE-22 and Re-25, and pressures were mild enough to permit reusing the cases up to ten times. In general the .308 Win. shines with medium burning rate powders and its advantage is for target shooting. I'd choose the .30-06 any day over the .308 for hunting big game. For this reason it is very popular in Africa for plains game.