243 with 80 grain soft point WW ammo would flop em no where near the spine.
I got chewed out if I got close to the spine as a bit more and I"d ruin meat... same with shoulders.
Not saying that all agree with that, but its how I was taught. 243 and 6mm accounted for untold deer from 3-4th grade onward for me... at least 3-5 a year..
the 300 was no better and actually a worse killer in some ways.
But I shoot 308 a LOT nowdays. I like what it has to offer. But the 257 wtby is getting a 2nd look due to some unknown bullet issues with the 308 the last 2 years that I finally got figured out...
300 whisper will be the ticket this fall, excepting probably have the 257 along if I find have to make shots over 150 yards...