I've owned a few 243 Win & 6mm Rem. and used them on a few occasions on animals as big as whitetail deer with 100% success.
However I always insure I am using a premium bullet, the animals are standing, relaxed and broadside.
BUT, even with this, I would never advocate for the use of the .243 diameter bullet for anything bigger than 100 pounds. I've seen and helped others track way too many deer that were never recovered for a litany of reasons when shot with these bullets.
I truly believe this caliber requires a hunter with great discipline when used on animals bigger than a coyote or the tiny 10.
The old adage, 'Just because you could doesn't mean you should'.
With all of that, the below Dakota .243 Win is my favorite rifle (today).
Rifle on left....(enjoy just looking at her, carrying her in the woods and taking her to the range).
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