At 20" a 308 may not lose enough speed to matter. The fastest 308 I own is a 20" Tikka CTR. It shoots 20-30 fps faster than my 22" guns. A 30-06 will start with more speed. But when cut will lose more. At the end of the day, I'd still guess an 18-20" 30-06 will still be faster than an 18-20" 308. But the difference won't be as much as it would be if both had 22-24" barrels.
It wouldn't be worth 20-25% more recoil from the 30-06 plus it will be louder. I'd stay with 308 for what you want to do. To my way of thinking 30-06 doesn't start to be better than 308 until you get to 180 gr and heavier bullets.
My thoughts exactly.
A 150 grainish bullet and a shorter barrel is right in a 308’s wheelhouse for efficiency and taking advantage of a short action.
Thought I would give an update. 18” RAR shooting 155 Scenars @2876. This was only an average of 3 because that’s all I had left. Load of 26.5 TAC in FC brass is giving ejector marks so I back off 1/2 grain. Worked good on the one bear I shot with it.
Take this for what you want - but I have killed/been apart of kills of close to 25 big game animals over the last few years all with scenars (139s out of the creed and 150s out of the 7 mag) and you have to remember that scenars are hard - harder than most similar type bullets. I prefer to push them Fast and even better aim for heavy bone. I have had the 150s break shoulder bones on elk and moose and exit.
In the creedmoor - we push 139s at a hot 2840 and the 150s in the 7 mag at 3150.
If it was me - I’d shoot the 30/06 and push 155s fast.
Take this for what you want - but I have killed/been apart of kills of close to 25 big game animals over the last few years all with scenars (139s out of the creed and 150s out of the 7 mag) and you have to remember that scenars are hard - harder than most similar type bullets. I prefer to push them Fast and even better aim for heavy bone. I have had the 150s break shoulder bones on elk and moose and exit.
In the creedmoor - we push 139s at a hot 2840 and the 150s in the 7 mag at 3150.
If it was me - I’d shoot the 30/06 and push 155s fast.
The 308 load replicating you 6.5 velocity so far has proven effective, granted its on animal. This bear took two shots. The first was quartering away at about 100. The bullet exited between the front legs leaving an exit wound about 2" in diameter. No bone was hit. the second shot at about 30 yards was truly broadside leaving a half dollar size exit after hitting a far rib. After being present on 15 bears being shot from various distances, I've not witnessed a blood trail as large or as close to the impact spot as this one.
Cut my load back to 46gr of TAC, no preesure signs this time with an average velocity of 2832.
Velocity is your "pressure sign." IMO you're on the upper, outer edge of SAAMI pressures with that velocity with the 155 in an 18" bbl'd 308. I'd back off .5 to 1.0 grains personally.
“Perfection is Achieved Not When There Is Nothing More to Add, But When There Is Nothing Left to Take Away” Antoine de Saint-Exupery
