I see quite a few votes for the 6.5 creedmoor. I have to ask for those that have the experience, is it really a step up from a 243 when it comes to elk and moose? I would consider those two pretty neck and neck myself, but haven’t witnessed side by side on game.
100%
The difference is in the bullets that can be sent with the creedmoor.
Even a 6mm cdm is a step up from the 243.
Because of the cartridge design and twist rate, u can send substantially heavier (and longer) bullets and therefore be more accurate at greater distance.
Of course, a heavier bullet is only part of the equation. It has to be a bullet designed to do its job at the point where velocity and engagement distance meet. Its all about the bullet.
Traditional Monos need a lot of speed to expand so you need to be mindful of your distance. But a fragmenting bullet like the Nosler Partition or modern fragmenting monos like Hunter or Cutting edge will be effective at lower speeds.
I have engaged my share of animals with a 243, 6.5cdm, 7-08, and my GOAT 308. All of them died about the same, excepting that deer shot with copper monos at distances of over 250 with the 243 ran a bit before the toppled.
As much as I am confident that a quality 243 bullet would kill a moose effectively, i would point my 308 at it instead if I ever drew one again.
My 7yr old is still on the 223 (sub loads) but my wife now shoots the 243 with zero issues and has been hinting that a 6.5 cdm of her own would make a good gift for her upcoming birthday.
One rifle to rule them all for me has always been the 308 (loaded up and down) but i also have a 6.5 cdm and its really only sentimentality that keeps me reaching for the 308.
When i mentor a new shooter or hunter these days, the 6.5cdm is hard to look past.
Long post, sorry.